Metallics JFM20 10-32 x 3/8 in. Flat Head Slotted Machine Screws - Steel Zinc - Each

Yes. The Metallics JFM20 is a 10-32 UNF screw, 32 threads per inch, cut to ANSI/ASME B1.1, which is the thread used on device yokes, box ears, and plaster ring holes in the US electrical trade. At 3/8 inch long it is a short screw meant for mounting straight into tapped metal, not for stacking spacers or thick build-out. If you need to reach through a raised ring or extension, order a longer length.

It sits flush in a countersunk hole. The flat head measures 0.333 to 0.362 in. across the top and 0.098 to 0.116 in. in head height, dimensioned to ASME B18.6.3-1998, so an 82 degree countersink sized for a #10 flat head takes it level with the surface. If the plate or bracket you are fastening has a plain straight-drilled hole rather than a countersink, the head will stand proud and you want a pan or round head instead.

These are AISI 1006-1022 carbon steel with a zinc finish, which is a dry-location, indoor plating. It handles handling and incidental moisture but it is not a corrosion barrier for wet locations, exterior panels, or washdown areas. For those, specify a stainless machine screw in the same 10-32 x 3/8 size.

No. The JFM20 is marked not Buy American compliant and not ARRA compliant, with a multiple country of origin. If your project carries a domestic-sourcing clause, this part will not satisfy it and you need a domestically produced fastener.

It ships as a jar of 100 screws, with 100 as the order minimum. One jar is the smallest buy. Other sizes and quantities are available by request.

A slotted (flat blade) driver. The slot runs 0.05 to 0.06 in. wide and 0.034 to 0.053 in. deep, so a cabinet-tip blade in that thickness seats properly; an oversized blade will ride out of the slot. Slotted heads are what most device and cover plate work still uses, but note they will not take a Phillips or square bit, so if your crew is driving with impact drivers you may prefer a combo-head screw.

The JFM20 carries a 1200 lb minimum tensile strength, with hardness at Rockwell B70-B100. That is the screw's own tensile capacity in straight pull, not an assembly rating, so the weaker link on most jobs is the tapped material or sheet metal it threads into. Note that the hardness and tensile figures Metallics publishes for stainless machine screws are guides only, since there is no national standard for those performance requirements on stainless.

Metallics lists the field application as the electrical, plumbing, heating and air conditioning industries, so the same 10-32 x 3/8 screw covers panel and device mounting, duct accessory brackets, and equipment covers. The zinc yellow version of this screw family is common in electronics work. For an MRO stockroom running all three trades, one jar of 100 covers a lot of small-fastener calls.