Metallics QDS182 10 x 1 in. 5/16 Hex Head Quadrive Sharp Point Tapping Screws - Steel Zinc - Each

The QDS182 has a 5/16 inch hex head with a Quadrive recess, so you can drive it four ways: a 5/16 hex driver or nut setter, a slotted bit, a Phillips bit, or a square bit. On a ladder with a cordless driver, most electricians run the 5/16 magnetic nut setter and seat it against the hex washer; the recess is there as a backup when you cannot get a nut setter on the head.

It is a sharp point tapping screw, not a self-drilling (drill point) screw. The sharp point will start in wood, drywall, and thin light-gauge sheet metal on its own, but it will not cut its own hole in heavier steel the way a self-drilling point does. For thicker metal, drill a pilot first or switch to a drill-point screw.

The QDS182 is zinc plated steel, which is a dry-location and interior finish. Zinc plating gives light corrosion resistance for indoor work and covered areas, but it is not stainless and it is not hot-dip galvanized, so it is the wrong choice for direct weather exposure, wet locations, coastal air, or treated lumber. Use stainless or hot-dip galvanized fasteners there.

A #10 diameter by 1 inch long screw with a 5/16 inch hex head. The 1 inch length is the common pick for mounting straps, device boxes, clamps, and 1-hole conduit supports to wood studs or framing where you want solid thread engagement without punching through the far side of a 2x.

A 5/16 hex head seats in a nut setter and will not cam out the way a Phillips does when you are driving overhead or one handed off a ladder. The washer face under a hex head also spreads load on strap and bracket flanges. The QDS182 adds the Quadrive recess on top of the hex, so you keep the slotted, Phillips, or square option if a nut setter will not reach the location.

The QDS182 is sold each, so you can take exactly the count you need rather than a full carton. There is a single model on it, QDS182, in the #10 x 1 inch 5/16 hex head configuration, so there is no size or finish to select when you order.

Yes, the Metallics QDS182 is manufactured in the USA. That matters on public and institutional jobs where domestic sourcing is written into the spec for fasteners.