Metallics JSPMP7SS 10-24 x 1 in. Pan Head Phillips Machine Screws - 18-8 Stainless - Each

Yes. 10-24 is the standard thread used for mounting devices, covers, and plates to steel outlet boxes and plaster rings, and the Metallics JSPMP7SS is a 10-24 thread with 24 threads per inch. At 1 inch long it gives you more reach than the short screws that ship in a box, which is what you want when you are picking up through a ring or a thick mud ring stack.

Yes. The JSPMP7SS is built to ASME B18.6.3-2010, the dimensional standard for slotted and recessed head machine screws, with SAE as the material standard. Tensile strength is listed at 80,000 psi minimum, though stainless machine screw strength figures are approximations since there is no single performance standard for stainless screws.

No. The JSPMP7SS is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. If your project carries a domestic-sourcing requirement, these will not satisfy it.

A #2 Phillips. The recess on the JSPMP7SS pan head measures 0.192 inch in diameter with a gaging depth of 0.089 to 0.113 inch, which is standard #2 territory. Using a #1 will cam out and chew the recess, especially in stainless.

The JSPMP7SS is 18-8 stainless, an austenitic grade that resists rust in wet and outdoor-exposed work, so it holds up in damp locations, wet-location enclosures, and coastal-adjacent exterior mounting far better than a plated steel screw. For direct saltwater immersion you would step up to 316.

It will not sit flush. A pan head is a raised head by design, and this one runs 0.122 to 0.133 inch in head height with a head width of 0.357 to 0.373 inch. If you need the head buried in the material, you want a flat head countersunk screw instead. Under a cover plate with a relieved screw boss the pan head is normally fine.

They ship in a jar of 100, and 100 is the order minimum. The jar weighs 0.9 lbs. That is the quantity to plan around if you are stocking a truck or a shop bin rather than buying loose pieces.

They are rated for electrical, plumbing, heating and air conditioning work. A machine screw with a 10-24 thread is a general-purpose fastener into tapped holes or a nut, so the same jar covers panel and enclosure mounting, duct and equipment brackets, and strut fittings. The 18-8 stainless is what makes it suitable where a plated screw would rust.

18-8 stainless is softer than a hardened steel screw, listed here at Rockwell BBS-B9S, so it can gall or seize in a stainless tapped hole if you drive it fast and dry. Use a #2 Phillips, keep the speed down, and seat it by hand at the end. Galling is not an issue threading into a steel box or a standard device yoke.