Metallics JSTSP15SS316 Screw 8-15 x 1 PN PH TS 316 SS (Jar 100)

Yes. The JSTSP15SS316 is 316 stainless steel, the marine grade with molybdenum added, so it handles salt spray, chlorides, and wash-down environments better than 18-8 or 304 stainless. It's the grade specified for coastal exterior electrical work, rooftop runs, pool and water treatment rooms, and food processing wash-down areas.

100 screws per jar. The jar pack is the usual way these go onto a service van or into an MRO bin, since the lid keeps the stainless hardware separated from carbon steel fasteners that would cross-contaminate and rust-stain them.

Stainless against galvanized steel is the standard practice and the usual pairing for exterior electrical mounting, because the zinc coating is the sacrificial member and there's far more of it than there is screw. Where you have to be careful is the other direction: a plain or zinc-plated carbon steel screw into a stainless or aluminum assembly will go first. If you're mounting aluminum enclosures or extrusion in a coastal setting, 316 like the JSTSP15SS316 is the grade to use, with an isolating washer if the spec on the drawing calls for one.

Both resist rust, but they are not interchangeable where chlorides are present. 18-8 (304) is the general purpose stainless and is fine for most interior and sheltered exterior work. 316, which is what the JSTSP15SS316 is made from, adds molybdenum and holds up in salt air, de-icing salt spray, and chemical wash-down. If an institutional or coastal spec says 316, an 18-8 screw is a substitution the inspector can reject, and it will pit in service.

Order Metallics JSTSP15SS316. That single part number covers the #8-15 x 1 inch pan head Phillips screw in 316 stainless, jar of 100, and it is the only configuration under that number, so there's no finish or length option to specify.

One inch of length gives enough bite into wood studs, blocking, or plywood backboards for mounting boxes, straps, and clamps, and the #8 pan head gives a broad bearing face so it won't pull through a stamped steel strap. For thicker stock or a lag-type pull-out load you'd step up in diameter rather than rely on a #8.

Phillips. Stainless is softer than hardened carbon steel, so seat the bit fully and drive at moderate speed, an impact driver run wide open is the fastest way to cam out and chew the recess on a stainless Phillips head.