Metallics JRM23 8-32 x 4 in. Round Head Combo Machine Screws - Steel Zinc - Each

No. The JRM23 is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. On a federally funded project with domestic sourcing requirements, you will need a fastener that carries that compliance.

Either works. The JRM23 head is a combo, carrying both a slot and a Phillips recess in the same head, so you can drive it with a flat blade or a Phillips. The Phillips recess takes a #2 driver. Slot width runs 0.045 to 0.054 in. and slot depth 0.058 to 0.077 in., so a standard small flat tip seats properly.

The JRM23 ships 100 to a jar, and 100 is the order minimum, so it is sold as a full jar rather than loose by the piece. The jar weighs 2.01 lbs.

The JRM23 is steel with a zinc finish, which is a plating meant for dry indoor use. It gives light corrosion resistance for handling and normal interior conditions, not for wet, exterior, or coastal exposure. For damp or outdoor work, specify a stainless machine screw in the same 8-32 x 4 in. size instead.

Minimum tensile strength on these is 60,000 psi, with hardness at Rockwell B70-B100, made from AISI 1006-1022 low carbon steel. That is standard commercial machine screw material, fine for mounting devices, straps, covers, and light fixtures. It is not a structural or high strength fastener, so do not substitute it where a graded bolt is specified.

Round head, so it sits proud of the material rather than flush. Head height measures 0.107 to 0.12 in. and head width 0.287 to 0.309 in. If you need the fastener flush or countersunk, a round head is the wrong choice; use a flat head machine screw in the same 8-32 thread.

Metallics lists the JRM23 for electrical, plumbing, heating and air conditioning work. In practice the extra length is for reaching through built up thickness: deep plaster rings, extension rings, fixture canopies and spacers, or air handling and duct mounted accessories where the screw has to cross a gap before it picks up threads.

The Phillips recess runs 0.165 to 0.178 in. in diameter, 0.075 to 0.101 in. deep, with a 0.03 in. recess width and recess penetration gaging depth of 0.064 to 0.090 in. That is a full standard #2 recess, so a #2 bit seats to depth. On a combo head, keep the torque modest; the slot that shares the head reduces the material supporting the recess.