Coloured 4.2 x 13mm Hex Head Self-Drilling Tek Screws
These 4.2 x 13mm coloured hex head self-drilling tek screws are built for steel-to-steel fixing where a high-torque hex drive and strong clamping force are required on visible structural metalwork. The hex washer face spreads load across the steel substrate, and the 1/4" hex drive delivers the torque transfer that Phillips and Pozidriv recesses cannot match - making these the specification for cladding rail systems, metal roofing connections, and structural steelwork where the fixing needs to hold and the head stays in view.
The self-drilling Tek point cuts directly into light-gauge steel up to 3.0mm thick without pre-drilling, and the 13mm length keeps protrusion behind the substrate to a minimum on thin steel connections. These screws are designed exclusively for steel-to-steel applications - for timber, plastic, or composite panel substrates, the flange head or wafer head self-tapping ranges are the correct specification.
Manufactured from carbon steel with a bright zinc plated (BZP) base and finished in a durable RAL powder coat, each hex head is colour-matched to the steelwork it sits against. On exposed structural metalwork, cladding rails, and roofing systems, a bright zinc hex head stands out against colour-specified steelwork as a cold, metallic intrusion. A colour-matched hex head sits within the surface rather than against it, maintaining the finish across every visible fixing point.
41 RAL Colour-Matched Finishes
Every 4.2 x 13mm hex head tek screw is electro-statically powder-coated and oven-cured to a RAL Classic colour standard. The result is a hard, uniform finish bonded directly to the hex head and washer face - resistant to scratching, chipping, UV fading, and general site wear. Unlike wet paint, powder coat will not peel, blister, or thin at edges over time, even on fully exposed external steelwork.
With 41 stocked RAL colours spanning whites, greys, blacks, blues, greens, reds, yellows, browns, and purples, these coloured hex head tek screws cover the most commonly specified colours across structural steelwork, cladding, and roofing applications. Whether you are matching RAL 7032 Pebble Grey cladding rails, RAL 7016 Anthracite Grey structural steelwork, RAL 9005 Jet Black roof connections, or RAL 6005 Moss Green agricultural frameworks, the right colour is available for immediate dispatch.
Need a RAL colour outside the stocked range? We hold over 400 RAL Classic powders and can coat to any colour on request. Contact us with your RAL reference for availability and lead times.
Common Applications
4.2 x 13mm coloured hex head self-drilling tek screws are used wherever a colour-matched, high-torque fix into steel is required:
- Structural steelwork - cladding rail systems, framework connections, and exposed steel fixings
- Metal roofing - roof sheet connections, flashings, ridge caps, and roof structure fixings
- Industrial and agricultural buildings - barn steelwork, portal frame cladding rails, and equipment fixings
- HVAC and fabrication - ductwork connections, sheet metal assemblies, and fabricated metalwork
- Street furniture and public realm - support steelwork, bollard frames, and infrastructure fixings
Specification
| Size | 4.2 x 13mm |
| Thread Diameter | 4.2mm |
| Thread Size (imperial) | 8 x ½″ |
| Length | 13mm |
| Max Drilling Thickness (MDT) | 3.0mm |
| Head Type | Hex head, washer faced |
| Drive | ¼″ hex (6.35mm) |
| Point Type | Self-drilling (Tek) |
| Material | Carbon steel |
| Base Finish | Bright Zinc Plated (BZP) |
| Coating | RAL Classic powder coat (electrostatic, oven-cured) |
| Substrates | Steel, sheet metal (steel-to-steel only) |
| Colours Available | 41 stocked RAL colours (any RAL Classic on request) |
Frequently Asked Questions
What are hex head self-drilling tek screws used for?
They are designed for steel-to-steel fixing applications - structural steelwork connections, cladding rail systems, metal roofing sheets, flashings, HVAC ductwork, and fabricated metalwork where a high-torque hex drive and strong clamping force are required. The self-drilling Tek point cuts directly into light-gauge steel up to 3.0mm without pre-drilling.
Can these tek screws be used on timber or plastic?
No. These hex head self-drilling tek screws are designed for steel-to-steel applications only. The Tek point and thread geometry are optimised for metal substrates. For timber, plastic, or composite panel substrates, use the RALfixings flange head or wafer head self-tapping screw ranges instead.
What thickness of steel can these screws drill through?
The self-drilling Tek point is rated for light section steel up to 3.0mm thick. It cuts its own hole and forms the thread as it is driven into the substrate, removing the need to pre-drill. For substrates thicker than 3.0mm, a different fixing specification is required.
What driver do I need for these screws?
These hex head tek screws take a 1/4" (6.35mm) hex drive. They are compatible with standard impact drivers fitted with a 1/4" hex socket and hex socket nut runners. No Phillips or Pozidriv bit is required.
What is the difference between a hex head tek screw and a wafer head self-drilling screw?
Both have self-drilling Tek points for fixing into steel without pre-drilling, but the head type and drive differ. The hex head provides higher torque transfer and stronger clamping force through the washer face - suited to structural steelwork, cladding rails, and roofing connections. The wafer head sits lower and flatter against the surface - suited to hoarding, signage, and visible panel fixings where minimal head protrusion and a discreet finish matter more than raw clamping force.
Powder Coated Hex Head Tek Screws
RALfixings specialise in colour-matched visible fixings for the cladding, roofing, and structural steelwork sectors. Every tek screw is powder-coated in-house using an electrostatic spray process, then oven-cured at 200°C to produce a hard, even finish that bonds directly to the hex head and washer face.
Powder coating outperforms wet paint in every measurable way. The electrostatically charged powder particles wrap around the hex head profile and across the washer face, building a consistent film thickness that liquid paint cannot replicate. On exposed structural steelwork - where hex heads are visible at regular intervals across cladding rails and roofing connections - batch-to-batch colour consistency is what holds the finish together. The cured finish is harder, more flexible, and far more resistant to impact, abrasion, and chemical exposure than paint, lasting years beyond a conventional painted finish in fully exposed exterior conditions.
Benefits of powder coated hex head tek screws:
- Scratch resistant - hard cured finish withstands handling, installation, and tool contact
- Rust resistant - BZP base plus powder coat provides dual corrosion protection
- UV resistant - colour stays true with no fading or chalking
- Weather resistant - will not peel, blister, or crack in exterior conditions
- Colourfast - consistent colour across production runs and pack sizes
Available RAL Colours
13mm x 4.2mm coloured hex head self-drilling tek screws are stocked in the following 41 RAL Classic colours. Select your colour from the dropdown above, or view the full RALfixings colour guide for additional RAL colours available on request.
- RAL 1013 Oyster White
- RAL 1015 Light Ivory
- RAL 1016 Sulphur Yellow
- RAL 1019 Grey Beige
- RAL 1020 Olive Yellow
- RAL 1023 Traffic Yellow
- RAL 1033 Dahlia Yellow
- RAL 1036 Pearl Gold
- RAL 3002 Carmine Red
- RAL 3004 Purple Red
- RAL 3009 Oxide Red
- RAL 3020 Traffic Red
- RAL 4006 Traffic Purple
- RAL 4007 Violet Purple
- RAL 4010 Telemagenta
- RAL 5003 Sapphire Blue
- RAL 5004 Black Blue
- RAL 5012 Light Blue
- RAL 5013 Cobalt Blue
- RAL 5023 Distant Blue
- RAL 5024 Pastel Blue
- RAL 6003 Olive Green
- RAL 6005 Moss Green
- RAL 6009 Fir Green
- RAL 6012 Black Green
- RAL 6016 Turquoise Green
- RAL 6024 Traffic Green
- RAL 6025 Fern Green
- RAL 6027 Light Green
- RAL 7009 Green Grey
- RAL 7016 Anthracite Grey
- RAL 7032 Pebble Grey
- RAL 7035 Light Grey
- RAL 7038 Agate Grey
- RAL 7042 Traffic Grey A
- RAL 8004 Copper Brown
- RAL 8008 Olive Brown
- RAL 8019 Grey Brown
- RAL 9005 Jet Black
- RAL 9010 Pure White
- RAL 9016 Traffic White
Coloured 4.2 x 13mm Hex Head Self-Drilling Tek Screws
These 4.2 x 13mm coloured hex head self-drilling tek screws are built for steel-to-steel fixing where a high-torque hex drive and strong clamping force are required on visible structural metalwork. The hex washer face spreads load across the steel substrate, and the 1/4" hex drive delivers the torque transfer that Phillips and Pozidriv recesses cannot match - making these the specification for cladding rail systems, metal roofing connections, and structural steelwork where the fixing needs to hold and the head stays in view.
The self-drilling Tek point cuts directly into light-gauge steel up to 3.0mm thick without pre-drilling, and the 13mm length keeps protrusion behind the substrate to a minimum on thin steel connections. These screws are designed exclusively for steel-to-steel applications - for timber, plastic, or composite panel substrates, the flange head or wafer head self-tapping ranges are the correct specification.
Manufactured from carbon steel with a bright zinc plated (BZP) base and finished in a durable RAL powder coat, each hex head is colour-matched to the steelwork it sits against. On exposed structural metalwork, cladding rails, and roofing systems, a bright zinc hex head stands out against colour-specified steelwork as a cold, metallic intrusion. A colour-matched hex head sits within the surface rather than against it, maintaining the finish across every visible fixing point.
41 RAL Colour-Matched Finishes
Every 4.2 x 13mm hex head tek screw is electro-statically powder-coated and oven-cured to a RAL Classic colour standard. The result is a hard, uniform finish bonded directly to the hex head and washer face - resistant to scratching, chipping, UV fading, and general site wear. Unlike wet paint, powder coat will not peel, blister, or thin at edges over time, even on fully exposed external steelwork.
With 41 stocked RAL colours spanning whites, greys, blacks, blues, greens, reds, yellows, browns, and purples, these coloured hex head tek screws cover the most commonly specified colours across structural steelwork, cladding, and roofing applications. Whether you are matching RAL 7032 Pebble Grey cladding rails, RAL 7016 Anthracite Grey structural steelwork, RAL 9005 Jet Black roof connections, or RAL 6005 Moss Green agricultural frameworks, the right colour is available for immediate dispatch.
Need a RAL colour outside the stocked range? We hold over 400 RAL Classic powders and can coat to any colour on request. Contact us with your RAL reference for availability and lead times.
Common Applications
4.2 x 13mm coloured hex head self-drilling tek screws are used wherever a colour-matched, high-torque fix into steel is required:
- Structural steelwork - cladding rail systems, framework connections, and exposed steel fixings
- Metal roofing - roof sheet connections, flashings, ridge caps, and roof structure fixings
- Industrial and agricultural buildings - barn steelwork, portal frame cladding rails, and equipment fixings
- HVAC and fabrication - ductwork connections, sheet metal assemblies, and fabricated metalwork
- Street furniture and public realm - support steelwork, bollard frames, and infrastructure fixings
Specification
| Size | 4.2 x 13mm |
| Thread Diameter | 4.2mm |
| Thread Size (imperial) | 8 x ½″ |
| Length | 13mm |
| Max Drilling Thickness (MDT) | 3.0mm |
| Head Type | Hex head, washer faced |
| Drive | ¼″ hex (6.35mm) |
| Point Type | Self-drilling (Tek) |
| Material | Carbon steel |
| Base Finish | Bright Zinc Plated (BZP) |
| Coating | RAL Classic powder coat (electrostatic, oven-cured) |
| Substrates | Steel, sheet metal (steel-to-steel only) |
| Colours Available | 41 stocked RAL colours (any RAL Classic on request) |
Frequently Asked Questions
What are hex head self-drilling tek screws used for?
They are designed for steel-to-steel fixing applications - structural steelwork connections, cladding rail systems, metal roofing sheets, flashings, HVAC ductwork, and fabricated metalwork where a high-torque hex drive and strong clamping force are required. The self-drilling Tek point cuts directly into light-gauge steel up to 3.0mm without pre-drilling.
Can these tek screws be used on timber or plastic?
No. These hex head self-drilling tek screws are designed for steel-to-steel applications only. The Tek point and thread geometry are optimised for metal substrates. For timber, plastic, or composite panel substrates, use the RALfixings flange head or wafer head self-tapping screw ranges instead.
What thickness of steel can these screws drill through?
The self-drilling Tek point is rated for light section steel up to 3.0mm thick. It cuts its own hole and forms the thread as it is driven into the substrate, removing the need to pre-drill. For substrates thicker than 3.0mm, a different fixing specification is required.
What driver do I need for these screws?
These hex head tek screws take a 1/4" (6.35mm) hex drive. They are compatible with standard impact drivers fitted with a 1/4" hex socket and hex socket nut runners. No Phillips or Pozidriv bit is required.
What is the difference between a hex head tek screw and a wafer head self-drilling screw?
Both have self-drilling Tek points for fixing into steel without pre-drilling, but the head type and drive differ. The hex head provides higher torque transfer and stronger clamping force through the washer face - suited to structural steelwork, cladding rails, and roofing connections. The wafer head sits lower and flatter against the surface - suited to hoarding, signage, and visible panel fixings where minimal head protrusion and a discreet finish matter more than raw clamping force.
Powder Coated Hex Head Tek Screws
RALfixings specialise in colour-matched visible fixings for the cladding, roofing, and structural steelwork sectors. Every tek screw is powder-coated in-house using an electrostatic spray process, then oven-cured at 200°C to produce a hard, even finish that bonds directly to the hex head and washer face.
Powder coating outperforms wet paint in every measurable way. The electrostatically charged powder particles wrap around the hex head profile and across the washer face, building a consistent film thickness that liquid paint cannot replicate. On exposed structural steelwork - where hex heads are visible at regular intervals across cladding rails and roofing connections - batch-to-batch colour consistency is what holds the finish together. The cured finish is harder, more flexible, and far more resistant to impact, abrasion, and chemical exposure than paint, lasting years beyond a conventional painted finish in fully exposed exterior conditions.
Benefits of powder coated hex head tek screws:
- Scratch resistant - hard cured finish withstands handling, installation, and tool contact
- Rust resistant - BZP base plus powder coat provides dual corrosion protection
- UV resistant - colour stays true with no fading or chalking
- Weather resistant - will not peel, blister, or crack in exterior conditions
- Colourfast - consistent colour across production runs and pack sizes
Available RAL Colours
13mm x 4.2mm coloured hex head self-drilling tek screws are stocked in the following 41 RAL Classic colours. Select your colour from the dropdown above, or view the full RALfixings colour guide for additional RAL colours available on request.
- RAL 1013 Oyster White
- RAL 1015 Light Ivory
- RAL 1016 Sulphur Yellow
- RAL 1019 Grey Beige
- RAL 1020 Olive Yellow
- RAL 1023 Traffic Yellow
- RAL 1033 Dahlia Yellow
- RAL 1036 Pearl Gold
- RAL 3002 Carmine Red
- RAL 3004 Purple Red
- RAL 3009 Oxide Red
- RAL 3020 Traffic Red
- RAL 4006 Traffic Purple
- RAL 4007 Violet Purple
- RAL 4010 Telemagenta
- RAL 5003 Sapphire Blue
- RAL 5004 Black Blue
- RAL 5012 Light Blue
- RAL 5013 Cobalt Blue
- RAL 5023 Distant Blue
- RAL 5024 Pastel Blue
- RAL 6003 Olive Green
- RAL 6005 Moss Green
- RAL 6009 Fir Green
- RAL 6012 Black Green
- RAL 6016 Turquoise Green
- RAL 6024 Traffic Green
- RAL 6025 Fern Green
- RAL 6027 Light Green
- RAL 7009 Green Grey
- RAL 7016 Anthracite Grey
- RAL 7032 Pebble Grey
- RAL 7035 Light Grey
- RAL 7038 Agate Grey
- RAL 7042 Traffic Grey A
- RAL 8004 Copper Brown
- RAL 8008 Olive Brown
- RAL 8019 Grey Brown
- RAL 9005 Jet Black
- RAL 9010 Pure White
- RAL 9016 Traffic White
Delivery & Shipping Terms
1. Where We Deliver
We currently ship to addresses within the United Kingdom only.
If you require delivery outside the UK, this must be arranged in advance. Where international delivery is agreed:
- You are fully responsible for all import duties, taxes, and customs charges, including any fees for customs paperwork.
- RALfixings accepts no liability for customs delays or additional costs associated with international shipments.
2. Delivery Timescales
Our products fall into two categories: in-stock and made-to-order (bespoke) items.
In-Stock Items
- Usually dispatched within 1–2 working days.
- Delivery typically takes 1–3 working days from the dispatch date.
Powder Coated / Made-to-Order Items
- Typically dispatched within 3–5 working days, but may take up to 10 working days during busy periods.
- Delivery typically takes 1–3 working days after dispatch.
All quoted times are estimates, not guarantees. Delivery times may be affected by stock availability, courier performance, weather, or other factors beyond our control.
3. Shipping Costs
- Shipping charges are based on order weight and destination.
- The exact shipping cost will be shown at checkout before payment.
- Additional shipping charges may apply to remote areas or multiple consignments.
4. Tracking and Responsibility
All orders are shipped via tracked courier services to ensure maximum security and visibility.
Once your order has been dispatched:
- You will receive an order dispatch email letting you know your order is on it's way, and another email from Royal Mail or the chosen courier with your tracking information. If you have supplied a UK phone number you may also recieve a tracking text from Royal Mail or the chosen courier.
- Responsibility for the goods passes to you upon dispatch.
- RALfixings is not liable for loss or damage in transit. Please contact the courier directly with your tracking number if issues arise.
5. Missed Deliveries or Delays
If your parcel cannot be delivered and is returned to us:
- We can resend it, but an additional delivery charge will apply.
- We are not responsible for courier delays or failed delivery attempts.
If your order hasn’t arrived within the estimated delivery window, please contact us as soon as possible at info@ralfixings.com.
Order Amendments & Cancellations
Changing an Order
We begin preparing orders quickly — especially made-to-order items.
- If you need to amend your order, please contact us within 24 hours or as soon as possible.
- After this period, it may be too late to make changes as your order may already be in production or dispatched.
- If you wish to add items, and your order hasn’t yet shipped, we may be able to combine them. Otherwise, a new order (and delivery charge) will apply.
Returns & Refunds
1. Your Right to Cancel – B2C Customers Only
Under the Consumer Contracts Regulations 2013, B2C customers have the right to cancel certain purchases made online within 14 days of delivery.
However, this does not apply to:
- Bespoke or made-to-order goods — including all powder coated screws and fixings manufactured specifically for your order.
If your order includes stocked items only, you may cancel and return those goods within 14 days of receipt. You must:
- Inform us in writing via email within 14 days.
- Return the goods at your own cost, in their original condition and packaging.
- Ensure the items are received by us within 30 days of delivery.
We recommend using a tracked and insured delivery service for any returns, as we are not responsible for items lost or damaged in return transit.
2. Faulty or Incorrect Items
If you receive goods that are:
- Faulty, or
- Incorrectly supplied (e.g. wrong size, colour, or product)
Please notify us within 30 days of receiving the goods.
We will:
- Replace the items where possible, or
- Issue a refund if replacement is not appropriate.
You may be asked to return the faulty items for inspection before a refund or exchange is processed.
Once screws have been installed or used, they cannot be returned or refunded, unless faulty.
3. Refund Processing
- Refunds (where applicable) are processed within 5 working days of receiving the returned items.
- Refunds are only issued to the original payment method.
- Refunds cannot be made to a different card or by other means.
- Delivery charges are non-refundable unless your entire order was cancelled before dispatch or the goods were faulty or incorrect.
Returns Address
To return items, please send them to:
FAO: Jon Lett
RALfixings Ltd
26a Queens Road
Knaphill
Surrey
GU212DX
B2B Orders & Restocking Fee
The rights described above apply primarily to consumers (B2C). If you are a business customer (B2B), statutory cancellation rights under the Consumer Contracts Regulations do not apply.
Returns from business customers are accepted at our sole discretion, and only if agreed in writing before the goods are returned.
All authorised B2B returns are subject to a 15% restocking fee, which will be deducted from the final refund amount. This fee covers the cost of inspection, repackaging, and administrative processing.
Returned goods must be:
- In resaleable, unused condition
- In their original packaging
- Returned at the buyer’s expense via a tracked delivery service
We do not accept returns of any bespoke or made-to-order products under any circumstances unless the item is faulty.
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Coloured 4.2 x 13mm Hex Head Self-Drilling Tek Screws
These 4.2 x 13mm coloured hex head self-drilling tek screws are built for steel-to-steel fixing where a high-torque hex drive and strong clamping force are required on visible structural metalwork. The hex washer face spreads load across the steel substrate, and the 1/4" hex drive delivers the torque transfer that Phillips and Pozidriv recesses cannot match - making these the specification for cladding rail systems, metal roofing connections, and structural steelwork where the fixing needs to hold and the head stays in view.
The self-drilling Tek point cuts directly into light-gauge steel up to 3.0mm thick without pre-drilling, and the 13mm length keeps protrusion behind the substrate to a minimum on thin steel connections. These screws are designed exclusively for steel-to-steel applications - for timber, plastic, or composite panel substrates, the flange head or wafer head self-tapping ranges are the correct specification.
Manufactured from carbon steel with a bright zinc plated (BZP) base and finished in a durable RAL powder coat, each hex head is colour-matched to the steelwork it sits against. On exposed structural metalwork, cladding rails, and roofing systems, a bright zinc hex head stands out against colour-specified steelwork as a cold, metallic intrusion. A colour-matched hex head sits within the surface rather than against it, maintaining the finish across every visible fixing point.
41 RAL Colour-Matched Finishes
Every 4.2 x 13mm hex head tek screw is electro-statically powder-coated and oven-cured to a RAL Classic colour standard. The result is a hard, uniform finish bonded directly to the hex head and washer face - resistant to scratching, chipping, UV fading, and general site wear. Unlike wet paint, powder coat will not peel, blister, or thin at edges over time, even on fully exposed external steelwork.
With 41 stocked RAL colours spanning whites, greys, blacks, blues, greens, reds, yellows, browns, and purples, these coloured hex head tek screws cover the most commonly specified colours across structural steelwork, cladding, and roofing applications. Whether you are matching RAL 7032 Pebble Grey cladding rails, RAL 7016 Anthracite Grey structural steelwork, RAL 9005 Jet Black roof connections, or RAL 6005 Moss Green agricultural frameworks, the right colour is available for immediate dispatch.
Need a RAL colour outside the stocked range? We hold over 400 RAL Classic powders and can coat to any colour on request. Contact us with your RAL reference for availability and lead times.
Common Applications
4.2 x 13mm coloured hex head self-drilling tek screws are used wherever a colour-matched, high-torque fix into steel is required:
- Structural steelwork - cladding rail systems, framework connections, and exposed steel fixings
- Metal roofing - roof sheet connections, flashings, ridge caps, and roof structure fixings
- Industrial and agricultural buildings - barn steelwork, portal frame cladding rails, and equipment fixings
- HVAC and fabrication - ductwork connections, sheet metal assemblies, and fabricated metalwork
- Street furniture and public realm - support steelwork, bollard frames, and infrastructure fixings
Specification
| Size | 4.2 x 13mm |
| Thread Diameter | 4.2mm |
| Thread Size (imperial) | 8 x ½″ |
| Length | 13mm |
| Max Drilling Thickness (MDT) | 3.0mm |
| Head Type | Hex head, washer faced |
| Drive | ¼″ hex (6.35mm) |
| Point Type | Self-drilling (Tek) |
| Material | Carbon steel |
| Base Finish | Bright Zinc Plated (BZP) |
| Coating | RAL Classic powder coat (electrostatic, oven-cured) |
| Substrates | Steel, sheet metal (steel-to-steel only) |
| Colours Available | 41 stocked RAL colours (any RAL Classic on request) |
Frequently Asked Questions
What are hex head self-drilling tek screws used for?
They are designed for steel-to-steel fixing applications - structural steelwork connections, cladding rail systems, metal roofing sheets, flashings, HVAC ductwork, and fabricated metalwork where a high-torque hex drive and strong clamping force are required. The self-drilling Tek point cuts directly into light-gauge steel up to 3.0mm without pre-drilling.
Can these tek screws be used on timber or plastic?
No. These hex head self-drilling tek screws are designed for steel-to-steel applications only. The Tek point and thread geometry are optimised for metal substrates. For timber, plastic, or composite panel substrates, use the RALfixings flange head or wafer head self-tapping screw ranges instead.
What thickness of steel can these screws drill through?
The self-drilling Tek point is rated for light section steel up to 3.0mm thick. It cuts its own hole and forms the thread as it is driven into the substrate, removing the need to pre-drill. For substrates thicker than 3.0mm, a different fixing specification is required.
What driver do I need for these screws?
These hex head tek screws take a 1/4" (6.35mm) hex drive. They are compatible with standard impact drivers fitted with a 1/4" hex socket and hex socket nut runners. No Phillips or Pozidriv bit is required.
What is the difference between a hex head tek screw and a wafer head self-drilling screw?
Both have self-drilling Tek points for fixing into steel without pre-drilling, but the head type and drive differ. The hex head provides higher torque transfer and stronger clamping force through the washer face - suited to structural steelwork, cladding rails, and roofing connections. The wafer head sits lower and flatter against the surface - suited to hoarding, signage, and visible panel fixings where minimal head protrusion and a discreet finish matter more than raw clamping force.
Powder Coated Hex Head Tek Screws
RALfixings specialise in colour-matched visible fixings for the cladding, roofing, and structural steelwork sectors. Every tek screw is powder-coated in-house using an electrostatic spray process, then oven-cured at 200°C to produce a hard, even finish that bonds directly to the hex head and washer face.
Powder coating outperforms wet paint in every measurable way. The electrostatically charged powder particles wrap around the hex head profile and across the washer face, building a consistent film thickness that liquid paint cannot replicate. On exposed structural steelwork - where hex heads are visible at regular intervals across cladding rails and roofing connections - batch-to-batch colour consistency is what holds the finish together. The cured finish is harder, more flexible, and far more resistant to impact, abrasion, and chemical exposure than paint, lasting years beyond a conventional painted finish in fully exposed exterior conditions.
Benefits of powder coated hex head tek screws:
- Scratch resistant - hard cured finish withstands handling, installation, and tool contact
- Rust resistant - BZP base plus powder coat provides dual corrosion protection
- UV resistant - colour stays true with no fading or chalking
- Weather resistant - will not peel, blister, or crack in exterior conditions
- Colourfast - consistent colour across production runs and pack sizes
Available RAL Colours
13mm x 4.2mm coloured hex head self-drilling tek screws are stocked in the following 41 RAL Classic colours. Select your colour from the dropdown above, or view the full RALfixings colour guide for additional RAL colours available on request.
- RAL 1013 Oyster White
- RAL 1015 Light Ivory
- RAL 1016 Sulphur Yellow
- RAL 1019 Grey Beige
- RAL 1020 Olive Yellow
- RAL 1023 Traffic Yellow
- RAL 1033 Dahlia Yellow
- RAL 1036 Pearl Gold
- RAL 3002 Carmine Red
- RAL 3004 Purple Red
- RAL 3009 Oxide Red
- RAL 3020 Traffic Red
- RAL 4006 Traffic Purple
- RAL 4007 Violet Purple
- RAL 4010 Telemagenta
- RAL 5003 Sapphire Blue
- RAL 5004 Black Blue
- RAL 5012 Light Blue
- RAL 5013 Cobalt Blue
- RAL 5023 Distant Blue
- RAL 5024 Pastel Blue
- RAL 6003 Olive Green
- RAL 6005 Moss Green
- RAL 6009 Fir Green
- RAL 6012 Black Green
- RAL 6016 Turquoise Green
- RAL 6024 Traffic Green
- RAL 6025 Fern Green
- RAL 6027 Light Green
- RAL 7009 Green Grey
- RAL 7016 Anthracite Grey
- RAL 7032 Pebble Grey
- RAL 7035 Light Grey
- RAL 7038 Agate Grey
- RAL 7042 Traffic Grey A
- RAL 8004 Copper Brown
- RAL 8008 Olive Brown
- RAL 8019 Grey Brown
- RAL 9005 Jet Black
- RAL 9010 Pure White
- RAL 9016 Traffic White
Recommended applications
A colour-matched hex head tek screw for steel-to-steel fixing where high torque transfer and strong clamping force are needed on visible structural metalwork. The hex washer face spreads load across the steel substrate, and the 1/4″ hex drive delivers torque that Phillips and Pozidriv recesses cannot match - making this the specification for cladding rail systems, metal roofing connections, and exposed structural steelwork.
The self-drilling Tek point cuts directly into light-gauge steel up to 3.0mm thick without pre-drilling. The 13mm length keeps protrusion behind the substrate to a minimum on thin steel connections. Drive with a 1/4″ hex socket on an impact driver or nut runner.
These screws are for steel-to-steel applications only. For timber, plastic, or composite panel substrates, use the RALfixings flange head or wafer head self-tapping ranges. Where a lower-profile head is needed on visible panel fixings, our wafer head self-drilling screws offer the same Tek point with a flatter head profile.
Suitable for
In Stock
| Bulk Discount | ||
|---|---|---|
| 200+ | ||
| 500+ | ||
| 1000+ | ||
| 2000+ | ||
| 5000+ | ||
