CSK head self tapping screws are designed for clean, flush installation in wood, thin metal, plastic, and drywall. Their 90° countersunk head sits fully recessed to create a smooth finished surface, while sharp self-tapping threads eliminate the need for pre-drilling in most common materials. Built with consistent hardness and reliable thread geometry, these fasteners deliver stable clamping and long-term holding power in both indoor and outdoor assembly projects.
Countersunk head tapping screws are widely used in furniture production, light construction, cabinet assembly, and metal panel mounting. The optimized Phillips drive reduces cam-out during high-speed installation, and the tapered head aligns naturally with pre-countersunk holes for precise, professional results. This versatile CSK self tapping screw performs reliably across general fabrication, decorative finishing, and structural framing tasks.
| Thread Size (ST) | Thread Pitch | Head Dia. (max) | Head Height (max) | Length Range |
|---|---|---|---|---|
| ST2.2 (#4) | 0.8 mm | 4.2 mm | 1.8 mm | 6.5 – 25 mm |
| ST2.9 (#5) | 1.1 mm | 5.6 mm | 2.4 mm | 6.5 – 25 mm |
| ST3.5 (#6) | 1.3 mm | 7.0 mm | 2.6 mm | 6.5 – 50 mm |
| ST3.9 (#7) | 1.3 mm | 8.0 mm | 3.1 mm | 6.5 – 65 mm |
| ST4.2 (#8) | 1.4 mm | 8.0 mm | 3.1 mm | 9.5 – 75 mm |
| ST4.8 (#10) | 1.6 mm | 9.5 mm | 3.7 mm | 9.5 – 75 mm |
| ST5.5 (#12) | 1.8 mm | 11.0 mm | 4.0 mm | 9.5 – 85 mm |
| ST6.3 (#14) | 1.8 mm | 12.0 mm | 4.6 mm | 13 – 150 mm |
For thin metal panels (≤1.5 mm) and small plastic parts: choose ST2.9 to ST3.5 in short lengths.
For furniture, cabinet backs, and interior trim: ST3.9 to ST4.8 works best with medium lengths.
For wood framing, light steel studs, and drywall: select ST4.8 to ST6.3 for stronger clamping and pull-out resistance.
For outdoor, coastal, or industrial environments: use Ruspert®, Dacromet®, or 316 stainless steel finishes.
Always select a length that extends 5-8 mm beyond the material thickness to ensure full thread engagement. For thinner panels (<2mm), a shorter protrusion (3-5mm) may suffice to avoid bottoming out.
For hardwood or dense plastic over ST4.8, a small pilot hole is recommended to prevent material cracking.
Hefeng Group focuses on manufacturing and supplying screws for real construction needs.
Over the past 10 years, we’ve worked with customers across North America, South America, and Southeast Asia, learning that consistency matters most in this business...[ Read More >>]
