Metallics QTEKD13 10 x 1 in. 5/16 Head Quadrive Self-Drilling & Tapping Screws - #3 Drill Point - Domestic Steel Zinc - Each

The QTEKD13 is a #10 diameter screw, 1 inch long, with a 5/16 inch hex-style head and a Quadrive drive. The Quadrive head accepts a square (Robertson) driver as well as the 5/16 hex socket, so you can run them with a hex driver in an impact or with a square bit when the head is in a tight spot.

These are domestic steel with a zinc plating. Zinc plating handles indoor and dry locations fine, and it gives some protection in occasionally damp areas, but it is not a coating for sustained exterior exposure or wet locations. For roof work, exterior conduit racking, or anywhere continuously wet, step up to a stainless or a coated exterior-rated self-driller.

At 1 inch overall length, the QTEKD13 leaves roughly enough thread past the point to grab after the drill flutes clear the base metal, so it suits attaching strap, clips, box brackets, or thin plate to steel. If your combined stack of material is more than about half an inch, go to a longer screw so the full drill section can exit the hole and the threads can engage.

Yes. The QTEKD13 is domestic steel and made in the USA, which is what lets it be used on jobs carrying Buy American or domestic-material requirements for fasteners.

No pilot hole needed. It is a self-drilling and self-tapping screw, so the #3 drill point cuts the hole and the threads tap it in one pass. Run it at moderate speed with steady pressure; letting it spin without feeding is what dulls the point before it bites.

Metallics catalogs it as QTEKD13. That number covers the #10 diameter, 1 inch long screw with the 5/16 head, Quadrive drive, #3 drill point, and zinc-plated domestic steel.