Metallics JTEKD16 8 x 5/8 in. 1/4 Indented Hex Head Self-Drilling & Tapping Screws with Washer - #2 Drill Point - Steel Zinc - Each

The JTEKD16 is rated for panel thicknesses of 0.035 to 0.100 inch. That covers typical sheet metal studs, strut, duct flange and enclosure sheet steel. Go thicker than 0.100 inch and the #2 drill point is out of its range, so you want a heavier drill point or a pre-drilled and tapped hole instead.

No. It is a Type BSD self-drilling and tapping screw with a #2 drill point, so it cuts its own hole and forms its own thread in one pass through sheet metal. No pilot drilling, no tapping.

Yes on the hold. A 20 gauge stud is about 0.035 inch, which is the bottom of the 0.035 to 0.100 inch panel range this screw drills. The integral washer head is a bearing washer, 0.322 to 0.348 inch outside diameter and 0.019 to 0.031 inch thick, so it spreads load over thin sheet and resists pull-through. It is not a sealing washer, there is no rubber or neoprene bonded to it, so do not rely on it to weatherproof a penetration.

No. The JTEKD16 is not Buy American compliant and is not ARRA compliant, with multiple countries of origin. For federally funded work carrying domestic sourcing requirements you will need a fastener with a documented domestic origin.

It takes a 1/4 inch hex driver. The indented hex washer head measures 0.244 to 0.25 inch across the flats, 0.272 across the corners, with a head height of 0.096 to 0.11 inch. A standard 1/4 inch magnetic nut setter in an impact or screwgun drives it.

They ship in jars of 100, which is the order minimum. Packaging is a jar rather than a loose box, so the count stays intact on a service truck.

Minimum torsional strength is 42 lb-in, with a hardened case at Rockwell C32-40. That is enough for impact driving in the 0.035 to 0.100 inch sheet range, but back off the impact once the washer seats. Overdriving past seating is what shears heads, not the drilling itself.

They are steel with a zinc finish, which handles dry interior work, enclosures, strut and duct. Zinc plating is a light sacrificial coating, so for sustained exterior exposure, coastal air or wet locations you want stainless or a coated exterior fastener rather than plain zinc.

18 threads per inch on a #8 diameter, threads to SAE J78-2013 and head dimensions to ASME B18.6.3-2010. Steel is AISI 1016-1024. If a submittal calls out J78 drill screws, these match that callout.