Metallics JTEKD1SS 8 x 1/2 in. 1/4 Indented Hex Head Self-Drilling & Tapping Screws with Washer - #2 Drill Point - 410 Stainless Steel - Each

The Metallics JTEKD1SS is rated for panel thickness of 0.035 to 0.100 in. That covers typical sheet metal studs, strut, enclosure flanges and duct. Go thicker than 0.100 in. and the #2 point is out of range, so step up to a heavier drill point screw. Drill time runs about 2.5 seconds in a 1 mm plate.

No. The JTEKD1SS is not Buy American compliant and is not ARRA compliant, with multiple countries of origin. If your spec carries a domestic sourcing requirement, this is not the fastener to submit.

410 stainless is a hardenable martensitic grade, which is what lets the point drill its own hole, but it is only moderately corrosion resistant, not on the level of 300 series. It holds up fine in damp interior spaces, mechanical rooms and most protected exterior work. For coastal or chemical exposure, use a 300 series bi-metal drill screw instead.

A 1/4 in. hex driver or nut setter. The indented hex washer head measures 0.244 to 0.250 in. across the flats and 0.272 in. across corners, so a standard 1/4 in. magnetic nut setter in an impact or screwgun seats it. Head height is 0.096 to 0.110 in.

No separate washer needed. The head has an integral washer with an outside diameter of 0.322 to 0.348 in. and a washer thickness of 0.019 to 0.031 in., which spreads the load over strap holes, clips and sheet metal without crushing through.

These ship in a jar of 100, which is the order minimum. Other sizes and quantities are available by request.

18 threads per inch on a #8 diameter, which is the fine Type BSD self-drilling and tapping thread. That tighter pitch is what gives thread engagement in thin sheet, which is why the screw works down to 0.035 in. panel. Threads conform to SAE J78 - 2013.

Yes, that is the intended use. Metallics lists field application as the electrical, plumbing, heating and air conditioning industries. At 1/2 in. long with a #2 drill point, it suits attaching straps, clips, boxes, duct flange and hangers to light gauge metal without pre-drilling.

Minimum torsional strength is 42 lb-in, with a case hardness of Rockwell C38-46. Minimum torques are the same for stainless and steel self-drill screws. Keep the gun at moderate speed and back off once the washer seats, since over-driving past the rated torque is what shears heads off.

Dimensions are to ASME B18.6.3-2010 and threads to SAE J78 - 2013. Note that SAE J78 does not include specifications for #7 diameter drill screws, which matters if you are standardizing a fastener schedule across diameters.