Metallics QK16GR-10M 8 x 1-1/4 in. 1/4 Hex Head Slotted Sharp Point Self-Piercing & Tapping Screws - Gray - Steel Zinc - Each

No pilot hole. The QK16GR-10M is a sharp point self-piercing and tapping screw, so it pierces and forms its own thread in sheet metal as you drive it. The twin lead threads cut driving torque, and the undercut under the head lets more of the thread engage the material.

QK16GR-10M ships as a box with an order minimum of 10,000 pieces, which is the 10M in the part number. Metallics does make other sizes and quantities of the JQK self-piercing line available by request, so a smaller count is a different part number rather than a smaller buy of this one.

It is case-hard enough to form its own threads: hardness is Rockwell C28-38 on AISI 1018-1022 steel. That is the range self-piercing screws need to pierce light gauge steel like studs, duct, and channel without the point rolling over. It is not a concrete or masonry screw, and it is not meant for structural steel plate.

Metallics lists the QK16GR-10M as both ARRA compliant and Buy American compliant. Country of origin is recorded as multiple, so for a project that demands documented origin per shipment, ask for the cert on the lot you receive.

A 1/4 inch hex driver or nut setter. The head is hex with a measured width across flats of 0.244 to 0.25 inch and a head height of 0.096 to 0.11 inch. 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 a flat blade works for hand driving or backing one out in tight quarters.

The QK16GR-10M is steel with a zinc finish and a gray head color. Zinc plating handles interior and protected locations; it is not a stainless or hot-dip coating, so for direct weather exposure, coastal air, or wet locations a corrosion-resistant fastener is the better call.

Yes, the head carries a washer with an outside diameter of 0.322 to 0.348 inch and a thickness of 0.019 to 0.031 inch. That bearing surface spreads the clamp load over thin sheet and slotted strap, which is why it works on light gauge material where a plain hex head would pull through.

Self-piercing screws are not covered by a single dimensional standard the way ordinary tapping screws are, so Metallics publishes head, slot, and washer figures as ranges and calls them a guide. Deviation within those ranges is normal. If your spec calls out a fixed head height or width across flats, check the range against it before you commit the order.

15 threads per inch on a #8 diameter, 1-1/4 inch long screw. The coarse twin lead thread is what lets it tap its own hole quickly, and 1-1/4 inch of length gives you room to go through a box ear or strap plus the base metal.

The 10,000 piece box runs 60.8 lbs, with carton dimensions of 7.25 x 6.25 x 6 inches. Plan on it being a dense, two-hand box rather than a light one when you are staging material on a floor.