Metallics JQK19WCCL 8 x 2 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Gray - Steel Zinc - Each

No pilot hole is needed in thin sheet metal. The JQK19WCCL 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, which helps when you are running a lot of them overhead into studs or sheet metal framing.

It is a #8 diameter screw, 2 inches long, with 15 threads per inch. That TPI is coarse for a #8, which is what lets it tap its own thread in sheet steel rather than needing a tapped hole.

The screw runs Rockwell C28-38 case hardness on AISI 1018 to 1022 steel. That is the standard range for a case-hardened tapping screw: hard enough at the point to pierce and form thread in light gauge steel, with a core that still has some ductility. It is not rated for structural or heavy-plate work.

It takes a 1/4 inch hex nut driver. Head width measures 0.244 to 0.25 in. and head height 0.096 to 0.11 in. The head is also slotted, with a slot width of 0.045 to 0.054 and depth of 0.052 to 0.074, so a flat blade will back it out by hand if you cannot get a socket in tight quarters.

Yes, it has an integral washer face: outside diameter 0.322 to 0.348 in. and thickness 0.019 to 0.031 in. There is also an undercut beneath the head, which gives you more usable thread engagement than a plain pan head of the same length.

These ship in a jar with a 250-count minimum. The packed jar weighs 2.5 lbs and measures 3.5 in. wide by 3.5 in. long by 5.75 in. high, so it stores easily on a van shelf.

The finish is zinc plating on steel, which is a mild indoor corrosion coating. It suits dry interior electrical work, boxes, straps, and bracket mounting. For exterior, wet locations, or treated lumber, go to a stainless or a coated exterior-rated fastener instead.

They are flagged compliant for both ARRA and Buy American. Country of origin is listed as China, so if your specification requires domestic melt and manufacture rather than the compliance flag, confirm that against your contract language before you submit.

No. 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 for the JQK19WCCL (0.244 to 0.25 in. head width, 0.096 to 0.11 in. head height) are guide values and small deviations can occur. If you are matching an existing screw head for a countersunk or clearance detail, measure the one in hand.