Metallics JFMP70SS 10-24 x 1/2 in. Flat Head Phillips Machine Screws - 18-8 Stainless - Each

Yes. The Metallics JFMP70SS is a 10-24 UNC machine screw cut to the ANSI/ASME B1.1 thread standard, which is the thread used on device yokes, box ears and cover holes tapped 10-24. It has 24 threads per inch, so it will not start in a 10-32 tapped hole; check the tap before mixing the two on a job.

No. The JFMP70SS is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. For a job with a domestic preference clause you need a fastener certified to that requirement.

At 1/2 inch of screw under the head, there is enough thread for a plate or strap sitting against a tapped box ear or yoke, which is the usual electrical, plumbing and HVAC use for this screw. If you are stacking a mud ring plus a gasket plus a plate, the 1/2 inch runs out quickly and you want a longer 10-24 instead.

The head is a flat countersunk type measuring 0.333 to 0.362 in. across and 0.098 to 0.116 in. high, so it seats flush in an 82 degree countersink of that diameter. In a plain punched hole with no 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, so a #1 bit will cam out and chew the recess, and a #3 will not seat.

They are made from 18-8 stainless, which is specified for general atmospheric corrosion resistance and is used in food processing machinery and refrigeration equipment. 18-8 also holds its strength better than plain steel at somewhat elevated operating temperatures, which is why it gets used around mechanical rooms and roof-mounted equipment.

Rated at 1050 lb minimum tensile, with a hardness of Rockwell B85 to B95. Worth knowing for a spec job: there is no national performance standard for stainless machine screws, so those hardness and tensile figures are guides rather than a graded rating like you would get on a hex cap screw.

Pick the flat head when the fastener has to finish flush in a countersunk hole, such as a plate or trim that something slides across. If the hole is a plain drilled or punched hole with no chamfer, a round or pan head gives you more bearing surface and will not wedge the material. The JFMP70SS is the flush-mount option in the Metallics FM and FMP series.

Head, recess and thread geometry conform to ASME B18.6.3-1998 for dimensions, with threads to ANSI/ASME B1.1 and material called out to SAE. Gaging diameter is 0.313 with protrusion of 0.025 to 0.042 above gage, which is the recess check an inspector would run.

They ship in a jar of 100, and 100 is the order minimum. The jar weighs 0.44 lbs.