Self‑drilling Phosphated Screw 3.5x25 mm by Koelner/Rawlplug — container pack, 6 pcs

Self‑drilling phosphated screw 3.5x25 mm by Koelner/Rawlplug supplied in a container pack of 6 pieces. This fastener is designed to drill and form its own mating thread in thin sheet metal and certain composite panels without the need for a separate pilot hole. The phosphate surface treatment provides basic corrosion resistance and enhances lubricity for consistent thread forming and reliable holding power in light assembly and sheet metal applications.

Advantages

The self‑drilling point eliminates predrilling in many thin metal substrates, saving time on repetitive fastening tasks. The phosphate coating improves resistance to surface oxidation and reduces driving torque for smoother installation. Its compact 3.5x25 mm size balances holding strength with minimal material disruption, and the container pack of six keeps screws organized and ready for small jobs or sample use.

Suitable for

• Fastening thin steel sheets and light gauge metal panels
• Assembly of metal enclosures, ducts and brackets
• Attaching metal to metal or metal to certain composite substrates
• Small repair and light construction tasks where quick installation is needed

Key specifications

• Nominal diameter: 3.5 mm
• Length: 25 mm (overall)
• Head type: pan/washer style suitable for screwdriver or driver bit
• Drive type: compatible with common driver bits (e.g., Phillips or Pozidriv depending on variant)
• Point type: self‑drilling (integrated drill tip)
• Surface finish: phosphate coating for basic corrosion resistance and reduced driving friction
• Pack quantity: 6 pieces in a container

How to use

Select an appropriate driver bit that matches the screw drive. Position the screw perpendicular to the workpiece and apply steady axial pressure while driving at moderate speed so the self‑drilling tip can penetrate and form a mating thread. Avoid excessive speed or lateral force to prevent damage to the screw head or substrate. For thicker materials, check material compatibility and consider predrilling if the screw cannot form a proper thread.

Usage recommendations

Use these screws in dry or mildly corrosive indoor environments; apply additional protection or select a different surface treatment for prolonged outdoor exposure. Match screw length to material thickness to ensure adequate thread engagement without protrusion. Test on a scrap piece when working with composite panels to confirm suitability and driving technique.