Metallics JTEKD114 8 x 1-1/4 in. 1/4 Indented Hex Head Self-Drilling & Tapping Screws with Washer - #2 Drill Point - Steel Zinc - Each

The JTEKD114 is zinc plated steel, which is an indoor and protected-location finish. It is fine in dry mechanical rooms, ceilings, panels and interior metal framing. For exterior exposure, roof work, coastal air, or anywhere condensation sits on the fastener, step up to a stainless self-drilling screw instead; the plating on a zinc screw will rust at the drilled hole where the plating is cut.

Dimensions are to ASME B18.6.3-2010 and threads to SAE J78 - 2013. Material is AISI 1016 - 1024 steel, case hardened to Rockwell C32-40, with a minimum torsional strength of 42 lb-in. Both ARRA and Buy American compliance are flagged as compliant, which matters on federally funded work. Country of origin is listed as multiple.

No pilot hole. These are Type BSD self-drilling and tapping screws, so the drill point cuts the hole and the threads form in the same pass. Per the product data, drill time runs about 2.5 seconds for a 1 mm thick plate.

A 1/4 in. hex driver or magnetic nutsetter in an impact or screwgun. The head is an indented hex type measuring 0.244 to 0.25 in. across the flats and 0.272 in. across corners, with head height of 0.096 to 0.11 in. No bit tips, no cam-out.

The integral washer head spreads the clamp load so the screw does not pull through thin sheet or chew up a soft material being fastened down. Washer outside diameter is 0.322 to 0.348 in. with a thickness of 0.019 to 0.031 in. That bearing surface is what makes this head style a common pick for hanging strap, clips, and sheet metal to light gauge steel without adding a separate washer.

They ship in a jar with an order minimum of 50 each, so 50 pieces is the smallest quantity. Jar weight is listed at 0.36 lbs. Other sizes and quantities are available by request.

The JTEKD114 is a #8 diameter, 1-1/4 in. long screw. Length has to cover the material you are fastening plus the base steel plus at least three threads past the back of the panel for full engagement. Since the base panel it is rated for is 0.035 to 0.100 in. thick, that leaves roughly an inch of usable grip for whatever you are holding down, which suits straps, clips, boxes and brackets rather than thick stacked assemblies.

18 threads per inch on a #8 diameter. With a minimum torsional strength of 42 lb-in, the screw body will take normal driving torque, but on an impact driver it is easy to keep going past seating and strip the tapped threads in thin sheet. Set your clutch or back off the trigger once the washer seats.