Metallics QK1-5M 7 x 1/2 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Steel Zinc - Each

No pre-drilling. The QK1-5M is a sharp point self-piercing and tapping screw, so it pierces thin sheet metal and forms its own thread as it drives. Twin lead threads cut the driving torque, and the screw is hardened to Rockwell C28-38 so the point holds up through the sheet.

It is a 1/2 inch long #7 screw at 16 threads per inch, so grip length is short. Figure thin-gauge sheet work, metal studs, duct, and box mounting rather than stacked or heavy stock. The undercut beneath the head gives you more usable thread engagement than a standard tapping screw of the same length.

It ships as a box of 5,000 pieces, which is the order minimum. If you need a smaller count or a different length or diameter in this self-piercing line, other sizes and quantities are available by request.

No. The QK1-5M is flagged as not Buy American compliant and not ARRA compliant, with multiple countries of origin. On a federally funded project with domestic sourcing language, this screw will not satisfy it.

The head is a 1/4 inch hex measuring 0.244 to 0.25 inch across, so a 1/4 inch hex driver or nut setter seats it. It also has a slotted drive, slot width 0.039 to 0.048 inch and depth 0.04 to 0.062 inch, so a small flat blade works for hand starting or final snugging in tight spots. Head height runs 0.08 to 0.093 inch.

Yes, it has an integral washer face. Outside diameter runs 0.322 to 0.348 inch with a thickness of 0.017 to 0.029 inch, which spreads the clamp load over thin sheet so the head is less likely to pull through.

It is carbon steel with a zinc plating, made from AISI 1018 to 1022 steel. Zinc plate suits dry interior work. For sustained exterior exposure or wet environments, step up to a stainless or hot-dip galvanized fastener instead.

Not reliably. Head dimensions on self-piercing screws differ from standard tapping screws, and there is no single industry standard for self-piercing screw dimensions. The published head, slot, and washer ranges on the QK1-5M are a guide and small deviations can occur, so if a head height or washer OD is critical to your assembly, verify against the actual part.