🔩 A2 Stainless Steel Pozi Flanged Self-Tapping Screws – Flange Tappers No.6 to No.12 | BS 4174
🏷️ Brand: HomeDIYer Fastener | BS 4174 | A2-70 | Pozidrive Flanged Head
📌 Overview — Faster installation, no pre-drilling, and a clean flanged finish. Tired of dealing with separate washers or pilot holes in thin sheet metal, plastic, or soft wood? Our A2 Stainless Steel Pozi Flanged Self-Tapping Screws (BS 4174) combine a sharp self-tapping point with a wide flange head and Pozidrive recess. The flange eliminates the need for a separate washer, distributes clamping load, and prevents pull-through. The Pozidrive cross-slot provides better driver engagement and less cam-out compared to Phillips. Perfect for HVAC, automotive trim, signage, boat fittings, and general sheet metal assembly. Made from corrosion-resistant A2-70 stainless steel, these screws last outdoors and resist rust. Choose from No.6 to No.12 sizes – order any length you need.
✨ Key Features of A2 Stainless Pozi Flanged Self-Tapping Screws
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Pozidrive Recess (Type Z) – Improved driver engagement, reduced cam-out, and higher torque transfer compared to standard Phillips.
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Integral Wide Flange Head – Eliminates the need for separate washers; distributes load and prevents pull-through in soft materials.
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Self-Tapping Point – Cuts its own thread into sheet metal, plastic, or soft wood – no pre-drilling required for most applications (check material thickness).
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A2-70 Stainless Steel (304 equivalent) – Excellent corrosion resistance for outdoor, marine, and coastal environments.
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BS 4174 Standard – British standard for stainless steel self-tapping screws with flanged heads, ensuring dimensional consistency.
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US Imperial Sizes No.6 to No.12 – Common American thread gauges: No.6 (3.5mm), No.8 (4mm), No.10 (5mm), No.12 (6mm).
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Untreated Natural Finish – No coatings to chip; smooth stainless surface for a clean appearance.
📏 Technical Specifications – Pozi Flanged Self-Tapping Screws (BS 4174)
| Size (Imperial) |
Thread Diameter (mm) |
Head Diameter (mm) |
Head Height (mm) |
Drive Type |
| No.6 |
3.5 |
8.0 |
2.0 |
Pozidriv |
| No.8 |
4.0 |
8.0 |
2.2 |
Pozidriv |
| No.10 |
5.0 |
10.0 |
3.2 |
Pozidriv |
| No.12 |
6.0 |
13.0 |
3.3 |
Pozidriv |
💡 Length & ordering info: Screw lengths are measured from the underside of the head (does not include head height). Choose your preferred length (e.g., 1/2", 3/4", 1", 1-1/4", 1-1/2", up to 2" or longer metric equivalents) — sold as per your requirement. All screws are fully threaded. Contact us for bulk or custom-length orders.
🔧 Pozidriv vs. Phillips: Pozidriv bits have extra small ribs at 45° to the main cross. Use a genuine Pozidriv driver (marked “PZ”) for the best fit. Phillips drivers will work but may come out more easily. We recommend PZ bits for maximum torque and reduced slipping.
❓ Frequently Asked Questions – Pozi Flanged Self-Tapping Screws
Do I need to pre-drill holes before using these self-tapping screws?
🔧 For thin sheet metal (up to 1/8" / 3mm), plastic, and soft wood, no pre-drilling is required — the screw will tap its own hole. For thicker or harder materials, a pilot hole may be recommended to prevent splitting or driver overload. Always test on a scrap piece first.
What is the difference between Pozidriv and Phillips? Can I use a Phillips bit?
📐 Pozidriv (PZ) has a more square cross with additional small ribs, offering better engagement and less cam-out. A Phillips driver (PH) will fit loosely and may slip or damage the recess. We strongly recommend using a proper Pozidriv bit (PZ1 for No.6-8, PZ2 for No.10-12) for best results and to avoid stripping.
Can I use these screws outdoors or in marine environments?
🌊 Yes – A2-70 stainless steel (304 grade) provides excellent corrosion resistance for outdoor use, coastal areas, and freshwater marine applications. For continuous saltwater immersion, consider upgrading to A4 (316) stainless, but A2 is perfectly suitable for most exterior trim, boat accessories, and outdoor furniture.
What lengths are available? Can I order custom lengths?
📦 “Package Included: As per Your Choice” means you select the exact length you need when ordering. Common lengths range from 3/8" up to 2" (e.g., 10mm, 12mm, 16mm, 20mm, 25mm, 30mm, 40mm, 50mm). Custom lengths available upon request for bulk orders. Just let us know your requirement.
Are these screws suitable for use with plastic or composite materials?
✅ Yes. The sharp self-tapping point and wide flange make them ideal for plastics, fiberglass, and composites. The flange prevents pull-through, and the Pozidrive recess allows controlled torque to avoid over-tightening and cracking. Always use a pilot hole for hard or brittle plastics.
⚙️ HomeDIYer Fastener — Professional-grade stainless steel self-tapping screws. Order your exact size and quantity today.
