Metallics JQK19 8 x 2 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Steel Zinc - Each

No. The JQK19 is a sharp point self-piercing and tapping screw, so it pierces and forms its own thread in sheet metal without a pilot hole. Twin lead threads cut driving torque, and the screw body runs 15 threads per inch at a #8 diameter and 2 inch length.

The head is a 1/4 inch hex measuring 0.244 to 0.25 inches across, so a standard 1/4 inch magnetic nut setter drives it. It also has a slotted drive cut into the head, 0.045 to 0.054 inches wide and 0.052 to 0.074 inches deep, so a flat blade works for hand starting or final snugging in tight spots.

No. The JQK19 is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. If your job carries a domestic sourcing clause, this screw will not satisfy it.

There is a washer face under the hex head, 0.322 to 0.348 inches outside diameter and 0.019 to 0.031 inches thick. That is a bearing surface for load spread, not a rubber or neoprene sealing washer, so it is not a weatherproofing fastener. The head is 0.096 to 0.11 inches high, and an undercut beneath the head gives you more thread engagement in the material.

These ship in a jar of 100 and 100 is the order minimum, so it is a full jar rather than a loose count. Metallics lists other sizes and quantities as available by request if 2 inch #8 is not the length you need.

The JQK19 is carbon steel with a zinc finish, which is a general indoor and dry-location plating. For wet, coastal, or treated-lumber contact you want stainless or a heavier coating instead. Inside a building, on strut, sheet metal duct, boxes, and panel work, the zinc plating is what this screw is built for.

The screws are case hardened to Rockwell C28-38 and made from AISI 1018 to 1022 steel, which is the standard spec range for tapping screws that have to form their own thread in sheet steel. That hardness is what lets the point pierce without rolling over. It is still a sheet metal fastener, not a concrete or structural screw.

No, and Metallics says so directly: head dimensions on self-piercing screws differ from standard tapping screws, and there is no single industry standard for self-piercing screw dimensions. The figures given (1/4 inch hex head, 0.244 to 0.25 inch width, 0.096 to 0.11 inch head height) are a guide and small deviations can occur. If a fixture or clip has a tight head pocket, verify with a sample before ordering a full jar.

Metallics lists the JQK series for the electrical, plumbing, heating and air conditioning industries. In practice that is duct and sheet metal work, mounting boxes and straps, and hanging light gauge metal where you cannot get a drill bit in first.

The jar weighs 0.88 lbs. Package size is listed at 3 x 3.6 x 3 inches, which matters if you are kitting these into a van bin or a job box.