Metallics TEKD610M 10 x 3/4 in. 5/16 Indented Hex Head Self-Drilling & Tapping Screws with Washer - #2 Drill Point - Steel Zinc - Each

No. The TEKD610M is a Type BSD self-drilling and tapping screw, meaning the drill point cuts its own hole and the threads tap it in one pass through steel in the 0.035 to 0.110 inch range. Drill time runs about 2.5 seconds through a 1 mm plate.

Thread is #10-16 UNC, 16 threads per inch, made to SAE J78-2013 with head dimensions to ASME B18.6.3-2010. That 16 TPI is the self-drilling screw thread pitch, not the #10-24 or #10-32 machine screw pitch, so a standard #10 machine nut will not run on cleanly. These are meant to tap their own mating thread in sheet metal.

The washer head spreads clamp load over a wider footprint so the head does not pull through thin sheet metal or dimple it. Washer OD runs 0.384 to 0.414 inches with a thickness of 0.019 to 0.031 inches. It is formed as part of the screw, so there is no loose washer to hold while you drive.

These are steel with a zinc plated finish, which is a mild indoor corrosion coating. For interior electrical work, strut, enclosures, and dry framing it is the normal choice. Exterior, coastal, or wash-down locations call for a stainless or coated exterior fastener instead.

Minimum torsional strength is 61 lb-in on the TEKD610M, with case hardness at Rockwell C32-40 and core steel to AISI 1016-1024. Minimum torques are the same for stainless and steel self-drill screws, so switching material does not buy you more twist resistance. Set the clutch on your gun rather than running it hard into a stop.

At 3/4 inch overall, a good portion of the length is consumed by the #2 drill point before full thread engages, so plan on fastening thin assemblies, metal sheet to light steel framing, or a device or strap against a panel of 0.035 to 0.110 inches. If you are stacking two thick members or going through insulation or board, step up to a longer screw in the same series.

Both the Buy American and ARRA compliance fields on the TEKD610M are marked C, for compliant. Country of origin is listed as multiple, so if your specifying authority wants origin documentation per lot, request it with the order.

They ship boxed with a 10,000 piece order minimum, and the full carton weight is listed at 59.1 lbs. That makes this a job-lot or stockroom buy rather than a handful-of-screws purchase. Other sizes and quantities are available by request.