Metallics JQK15GRV 8 x 1 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Gray - Steel Zinc - Each

Either works. The JQK15GRV has a hex head measuring 0.244 to 0.25 inches across, so a 1/4 inch hex driver or nut setter seats on it, and the head is also slotted (slot width 0.045 to 0.054 inches, depth 0.052 to 0.074 inches) if you'd rather run it with a flat blade in tight spots. Electricians usually use the 1/4 hex socket for speed and switch to the slot where a socket won't clear.

That's exactly what the JQK15GRV is for. It's a sharp point self-piercing and tapping screw, so it pierces and cuts its own thread in sheet metal without a pilot hole. Twin lead threads cut driving torque, and the undercut under the head lets more thread engage the material. For heavier gauge steel or structural thickness you'd want a drill point (self-drilling) screw instead, since a sharp point relies on piercing thin stock.

It's a #8 diameter, 1 inch long screw with 15 threads per inch. The 1 inch length gives you working penetration for sheet metal and light framing attachment; subtract the thickness of what you're fastening through to see how much thread actually bites into the substrate.

The JQK15GRV has an integral washer-style head: washer OD runs 0.322 to 0.348 inches with a washer thickness of 0.019 to 0.031 inches, and overall head height is 0.096 to 0.11 inches. That spreads bearing load on thin sheet so the head doesn't pull through. It is not a bonded neoprene sealing washer, so for weather-exposed penetrations you'd pick a screw with an EPDM washer.

These ship in a jar, with a minimum of 500 count. The packed jar weighs 2.7 lbs. If you need a different size or count, Metallics makes other sizes and quantities in the JQK series available by request.

Case hardness on the JQK15GRV runs Rockwell C28-38, made from AISI 1018 to 1022 steel. That's the normal hardness band for a tapping screw driven into light gauge steel. Keep driver speed moderate and let the twin lead threads do the work; over-driving a #8 tapping screw is what shears heads, not the material spec.

The JQK15GRV carries a compliant flag for both ARRA and Buy American in the manufacturer data, while country of origin is listed as China. On federally funded work those two facts need to be reconciled against your specific contract clause, so submit the manufacturer's compliance letter with your package rather than relying on the flag alone.

No, and Metallics flags it. 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 figures (0.244 to 0.25 inch head width, 0.096 to 0.11 inch head height) are a guide and deviations can occur. If you're matching an existing fastener in a prepped hole or a close clearance, measure what's in the wall rather than assuming parity with a #8 tapping screw.

The head is painted gray over a zinc-plated steel screw, which is the usual match for gray-finish raceway, strut, and panel work. Shade can vary between manufacturers and lots, so if the heads will be visible on a finished wall, hold one against what's already installed before you commit a full jar.