Metallics JSTSP42 4 x 3/4 in. Pan Head Phillips Tapping Screws - 18-8 Stainless - Each

The pan head on the JSTSP42 runs 0.205 to 0.219 in. across and 0.07 to 0.08 in. tall, so it projects less than a tenth of an inch above the surface. That clears most cover plates and clamp brackets, but it is a surface-mount head, not a flush one. If the detail calls for the head to disappear into the material, you need a flat or oval head screw instead.

These are Type A tapping screws with a gimlet point, which means the screw forms its own thread as it drives into sheet metal or soft material. You still want a pilot hole sized to the material thickness; the gimlet point starts the hole and tracks straight, but it is not a self-drilling point that cuts through steel on its own. Thread count is 24 per inch.

Mechanically yes, but be aware of the metallurgy. Fastening 18-8 stainless into aluminum or steel can set up a galvanic couple in some environments, which corrodes the softer metal around the fastener. Outdoors, in damp vaults, or in coastal air, that matters. Dry interior work with these #4 x 3/4 in. screws generally does not.

No. The JSTSP42 stainless tapping screws are not Buy American compliant and are not ARRA compliant, and country of origin is listed as multiple. On a federally funded project with domestic sourcing language, these will not pass. Source a domestic fastener line for that work.

A #1 Phillips driver is the correct fit. The recess on these #4 x 3/4 in. pan head screws measures 0.109 to 0.122 in. in diameter at 0.078 in. deep, so a #2 bit will cam out and chew the recess on a small head like this. Keep a #1 bit in the pouch if you are running these on plates or boxes.

They ship as a jar, and the order minimum is 100 count. So the buying unit is the jar of 100, not a single screw. For MRO stock or a panel build where you are placing dozens of #4 screws, that is one line item on the order.

Head and recess geometry follow ASME B18.6.3-2013, and the thread form follows ASME B18.6.4, the tapping screw thread standard. If a spec sheet or submittal calls out either of those for a #4 pan head Phillips tapping screw, the JSTSP42 answers it.

Overall length is 3/4 in. on a #4 diameter shank, measured from under the pan head, since pan heads sit on top of the work rather than sinking in. With 24 threads per inch you get roughly eighteen threads of engagement over that length, so after you subtract material thickness there is plenty of bite left for sheet metal, boxes, and light brackets.