Metallics JFMP94 10-32 x 3 in. Flat Head Phillips Machine Screws - Steel Zinc - Each

The Metallics JFMP94 is a 10-32 UNF machine screw, 32 threads per inch, cut to the ANSI/ASME B1.1 thread standard. 10-32 is the thread used on outlet box tapped holes, device yokes, mud rings and plaster rings, so it mates with that prep. The 3 inch length is long enough to reach through deep extension rings or thick build-up; for a flush box you want a much shorter screw.

They ship as a jar of 100, and 100 is the order minimum, so there is no partial-jar purchase. One jar weighs 2.01 lbs.

Yes. Head and recess geometry follow ASME B18.6.3-1998 and the threads follow ANSI/ASME B1.1, with material to AISI 1006-1022. That is the combination a spec reviewer looks for on a machine screw submittal. Note they are not Buy American compliant and not ARRA compliant, with multiple countries of origin, so they will not satisfy a domestic-content requirement.

A machine screw has a straight, uniform 10-32 UNF thread and a blunt end: it needs a pre-tapped hole or a nut. If you are fastening into bare sheet metal or an untapped hole, this is the wrong type, use a self-drilling or sheet metal screw. For boxes, rings, enclosures and panels that are already tapped 10-32, the machine screw is correct, and it can be removed and reinstalled repeatedly without stripping the host thread.

Flat head means a countersunk head that finishes flush with the surface when the hole is chamfered for it. The head measures 0.333 to 0.362 in. across and 0.098 to 0.116 in. in height, so the countersink has to be at least that wide to pull the head level. Without a chamfer the head will stand proud by roughly the head height.

A #2 Phillips. The recess is 0.198 in. in diameter and 0.124 in. deep, which is the standard pocket a #2 bit seats in. Using a #1 will cam out and chew the recess.

These screws are plated steel, finish listed as zinc over AISI 1006-1022 carbon steel. Zinc plating handles dry interior and normally occupied spaces fine, but it is a sacrificial coating, not stainless, so it will eventually corrode in wet, exterior, or washdown locations. For those openings specify a stainless machine screw of the same 10-32 x 3 in. size instead.

Metallics lists them for electrical, plumbing, heating and air conditioning work. The 3 inch length is the one electricians reach for when a device has to be pulled through added wall thickness, tile, or a deep ring. The yellow zinc version of the same screw is common in electronics work.