Metallics JSPMP18SS 8-32 x 1 in. Pan Head Phillips Machine Screws - 18-8 Stainless - Each

Yes. The Metallics JSPMP18SS is an 8-32 UNC machine screw, which is the thread size used for device mounting and cover screws in standard outlet and switch boxes. Thread pitch is 32 threads per inch. At 1 inch long it gives plenty of reach for mounting devices through plaster rings or box extensions, and you can run it in deeper or back it out as the box depth requires.

The material is 18-8 stainless, so these hold up in damp, outdoor, and washdown locations where a plated steel machine screw would rust and seize. That makes them the usual pick for exterior device covers, marine and coastal work, and food-service or healthcare environments where corrosion is the failure mode.

A pan head sits on top of the surface, not in it, so plan for about 0.105 to 0.115 inch of head height above the material. Head width runs 0.306 to 0.322 inch, so the bearing surface covers a standard 8-32 clearance hole without a washer. If you need the fastener flush or below the surface, you want a flat head in a countersunk hole instead of this pan head.

They are built to ASME B18.6.3-2010, the dimensional standard for inch-series machine screws, with material called out to SAE. For public-agency and federally funded jobs, they are listed as ARRA compliant and Buy American compliant. Country of origin is multiple.

A #2 Phillips bit. The recess is a Phillips with a 0.175 inch recess diameter and a gaging depth of 0.071 to 0.097 inch, so a #2 seats fully. Using a #1 will cam out and chew the recess, which matters more on 18-8 stainless than on hardened steel because the softer stainless deforms rather than resisting the bit.

They ship in a jar of 100, and 100 count is the order minimum. Jar packaging is practical for a van or a shop bin where a loose box would spill. Other sizes and quantities are available by request.

Tensile strength on the JSPMP18SS is 80,000 psi minimum, with hardness reported as Rockwell BBS-B9S. Note that tensile figures for stainless machine screws are approximations, because there is no single performance standard for them. Where you need a graded, repeatable clamp load rather than corrosion resistance, use a hardened steel fastener to a strength grade instead.

No. A machine screw has a straight, uniform 8-32 UNC thread and a blunt end, so it needs a tapped hole or a mating nut. It will not self-start in unthreaded sheet metal. For that you want a self-tapping or sheet metal screw. Where you are mounting into an existing tapped boss, like a device yoke or a fixture housing, this is the right type.