The Metallics JDS84 is a Type A thread forming screw with a gimlet point, made to self-start in thin metal from 0.015 to 0.050 inch thick, or in resin-filled plywood. Thicker steel needs a different point and thread form, since the wide-spaced Type A thread relies on thin stock to form its own mating thread.

Either works. The JDS84 has an indented hex washer head with a slot, so it takes a 1/4 inch hex driver or a flat blade. Head width runs 0.244 to 0.250 inch across flats with 0.272 across corners, and the slot is 0.045 to 0.054 wide and 0.052 to 0.066 deep. On electrical work most people run it with a 1/4 inch magnetic bit and keep the slot as a backup for tight spots.

No. The JDS84 is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. On a federally funded job with domestic sourcing requirements, you'll need a domestically produced fastener instead.

Type A, which is what the JDS84 is, has wider spaced threads than a Type AB and a gimlet point. The coarser spacing means fewer threads engaging, which is what lets it start and form thread in very thin stock (0.015 to 0.050 inch). Type AB runs a finer pitch and is the better choice when you're going into slightly heavier gauge or want more pull-out in the same hole.

It's built for exactly that: light metal assembly such as electrical outlets, framing and other sheet metal. The screw is case hardened steel at Rockwell C28-38 with a minimum torsional strength of 39 lb-in, so it takes driving torque without shearing in thin gauge. Steel per AISI 1016-1024.

Yes, it's an indented hex washer head. The washer outside diameter is 0.322 to 0.348 inch with a washer thickness of 0.019 to 0.031 inch, and head height runs 0.096 to 0.11 inch. That bearing surface spreads load on thin sheet so the head doesn't pull through, and it means you don't need to add a loose washer.

The JDS84 ships as a jar of 100 screws, and the jar is the order minimum, so one jar is the smallest buy. Jar weight is 1.16 lbs. Other sizes and quantities can be had by request.

The finish is zinc plated steel, which is a general indoor corrosion coating. It suits interior light metal and electrical assembly work. For sustained exterior exposure or wet locations, specify a stainless or heavier coated fastener instead.