Metallics JQK15W 8 x 1 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Gray - Steel Zinc - Each

No pilot hole needed in thin sheet metal. The JQK15W is a sharp point self-piercing and tapping screw, so it pierces and forms its own thread as it drives. Twin lead threads cut the driving torque, and the undercut under the head gives you more thread engagement in the material.

Two options on the same screw: a 1/4 inch hex head, or the slot across the top. The hex measures 0.244 to 0.25 inch across, so a 1/4 inch hex driver or magnetic bit holder seats it; slot width is 0.045 to 0.054 inch with a 0.052 to 0.074 inch depth, which takes a standard narrow flat blade for hand work or final snugging in tight spots.

It is a #8 diameter, 1 inch long screw with 15 threads per inch. The 15 TPI twin lead thread is a coarse pitch meant for sheet metal and light gauge steel rather than a fine machine thread, so don't expect it to mate with a tapped #8-32 hole.

Yes, it is a hex washer head. The washer outside diameter runs 0.322 to 0.348 inch with a thickness of 0.019 to 0.031 inch, and head height is 0.096 to 0.11 inch. That flange spreads the clamp load on sheet metal and over slightly oversized or slotted holes without adding a loose washer to the job.

The JQK15W is made from AISI 1018 to 1022 steel case hardened to Rockwell C28-38, which is what lets a sharp point pierce and form threads in sheet steel instead of deforming. Finish is zinc plating for corrosion resistance in dry interior work; it is not a stainless screw, so exterior or wet locations are a different fastener.

The JQK15W carries a compliant flag for both ARRA and Buy American in the manufacturer data, with country of origin listed as China. For a federally funded project, run those two flags past your specifying authority, since the compliance basis and the origin need to line up with the clause in your contract.

Don't assume they interchange. Head dimensions on self-piercing screws differ from standard tapping screws, and there is no single industry standard for self-piercing screw head geometry. The published figures (0.244 to 0.25 inch hex across, 0.322 to 0.348 inch washer OD) are a guide, and small deviations occur, so if you are fitting into a counterbore or a tight clip, check an actual sample.

They ship in a jar of 100, and 100 count is the order minimum. The packed jar weighs 0.54 lbs. Handy for a van or a shop drawer rather than a bulk box, and other sizes and quantities are available by request.

The head color is listed as white over the zinc plated steel body, so it reads light against white or light gray panels, cover plates, and trim. If you need the fastener to disappear on a dark surface, this is the wrong finish choice.