Metallics JQK5V 8 x 1/2 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Steel Zinc - Each

No pilot hole needed. The JQK5V is a sharp point self-piercing and tapping screw, so it pierces thin sheet metal and forms its own thread as it drives. The twin lead threads cut driving torque, which matters when you are running hundreds of them into studs or duct. The screws are heat treated to Rockwell C28-38, hard enough to tap mild steel sheet.

The JQK5V is flagged compliant for both ARRA and Buy American in the manufacturer's data. Country of origin is listed as multiple, so if your specification requires documented origin on a specific lot, ask for the mill paperwork with the order.

Not necessarily. Head dimensions on self-piercing screws differ from standard tapping screws, and there is no single industry standard for self-piercing screw dimensions, so the published figures on the JQK5V are a guide and small deviations can occur. If you are matching an existing hole or a counterbored clearance, check the head width of 0.244 to 0.25 inch and the washer OD of 0.322 to 0.348 inch against what is in the part now.

A 1/4 inch hex driver fits it: the head measures 0.244 to 0.25 inch across. It is also slotted, with a slot width of 0.045 to 0.054 inch and slot depth of 0.052 to 0.074 inch, so you can finish or back one out with a flat blade if you cannot get a driver socket onto it. Head height runs 0.096 to 0.11 inch.

It is a short fastener, 1/2 inch overall at a #8 diameter with 15 threads per inch, so it is meant for fastening straps, clips, boxes and plates to sheet metal rather than into thick stock. The undercut area beneath the head gives a longer run of usable thread engagement than the head profile would suggest. For anything thicker than light sheet, step up to a longer length.

Yes, it has an integral washer face, 0.322 to 0.348 inch outside diameter and 0.019 to 0.031 inch thick. That spreads the load over the hole so the head will not pull through a slotted strap or a punched knockout flange.

No. The order minimum is 500 count, supplied in a jar. Other sizes and quantities are available by request.

Steel with a zinc finish, made from AISI 1018 to 1022 low carbon steel. Zinc plating is a dry indoor coating: fine inside panels, raceway, boxes and interior framing, but it is not a stainless or hot dip finish, so skip it for exterior or wet locations.

A jar runs 1.75 lbs, and the container measures 3 by 3 by 3.6 inches, so a full box of them stacks easily on a van shelf or in a job cart.