Metallics JSRM135 3/8-16 x 4 in. Round Head Slotted Machine Screws - 18-8 Stainless - Each

The JSRM135 is a 3/8-16 machine screw, 4 inches long, with 16 threads per inch. That is the standard coarse (UNC) pitch for 3/8 inch, so it mates with 3/8-16 tapped holes and standard 3/8-16 nuts.

Material is 18-8 stainless, the common austenitic grade used where plain steel or zinc plating would rust, so it suits damp interiors, exterior boxes and coastal-adjacent work. It is not hardened for strength the way a plated alloy screw is, with hardness at Rockwell B85-B95 and tensile strength rated 80,000 psi minimum.

No. The JSRM135 is not Buy American compliant and not ARRA compliant, and country of origin is listed as multiple. For a federally funded project with domestic sourcing requirements you will need a domestically produced fastener instead.

It will not sit flush. A round head stands proud of the surface by design, and on this screw the head measures 0.237 to 0.256 in. high and 0.67 to 0.708 in. across. If you need the head below the surface, you want a flat head screw in a countersunk hole instead.

They ship in a jar with a 50 piece minimum order quantity, priced each. So a single buy is 50 screws, not one, which is worth knowing if you only need a handful for one box or panel.

Treat it as an approximation. Metallics states that tensile values for stainless screws are approximations only because there is no single performance standard for stainless machine screws. For a load-bearing or structural connection, specify a fastener with a defined grade; these are intended for machine screw duty such as mounting enclosures, device plates, brackets and panel hardware.

At 4 inches, the JSRM135 is meant for deep stacks, through-bolting thick assemblies or standoff mounting, and it will leave a long tail if your tapped hole is shallow. Metallics offers other sizes and quantities in the SRM series by request, so a shorter 3/8-16 can be sourced.