Metallics JTEKDHH7 10 x 1 in. 5/16 High Hat Hex Head Self-Drilling & Tapping Screws with Washer - #3 Drill Point - Steel Zinc - Each

The JTEKDHH7 is flagged as both Buy American compliant and ARRA compliant in the manufacturer data. Country of origin is listed as multiple, so if your contract requires a specific origin on the submittal, that is the line to verify on the certificate.

No separate washer is required. The high hat washer head is integral, with a washer outside diameter of 0.364 to 0.414 inches. That spread gives more bearing surface than a plain hex head, which is what you want through strut, clip, or thin flange where a bare head would pull through or dish the metal.

Fastener length is 1 inch overall, and some of that is consumed by the drill point. Figure on the point and the first threads being used up cutting through the panel, so useful thread engagement after a 0.175 inch panel is still ample for standard sheet metal to sheet metal work. For stacking two framing members or going through a spacer, step up to a longer length in the same series.

The finish is zinc plating over steel, which is a dry indoor or protected interior finish. It handles normal building interiors, electrical rooms, and concealed work fine. For exterior exposure, wet locations, roof deck, or anywhere near coastal air, specify a stainless or coated exterior-rated drill screw instead, since plain zinc will bleed rust once the plating is scratched by the drilling action.

Threads are 16 per inch to SAE J78 - 2013, built from AISI 1016 to 1024 steel, case hardened to Rockwell C32-40 with a minimum torsional strength of 61 lb-in. The hardness is what lets the point cut steel without rolling over; the torsional figure is your margin before the screw snaps in a high-torque gun. Back the gun off once the washer seats.

No pilot hole. Type BSD means the screw drills and taps its own hole in one pass, which is the whole point of the #3 drill tip. Run it in one shot at steady pressure, no pecking, so the flutes clear the chip and the threads start before the point walks.

These ship in a jar with an order minimum of 100 count. Order quantity is handled in hundreds, so plan takeoffs in full jars rather than loose pieces.