Metallics JRM134 1/4-20 x 6 in. Round Head Combo Machine Screws - Steel Zinc - Each

Either a flat blade or a #3 Phillips. The JRM134 has a combination head, slotted and Phillips in the same round head, so you can drive it with whichever bit is already in your hand. The slot runs 0.064 to 0.075 inch wide and 0.082 to 0.109 inch deep, and the Phillips recess measures 0.255 to 0.268 inch across at 0.121 to 0.147 inch deep. A #3 Phillips is the called-out driver size; a #2 will cam out of a recess that size.

Yes. The JRM134 is cut 1/4-20, meaning a 1/4 inch nominal diameter at 20 threads per inch, which is the standard coarse UNC pitch for that diameter. It mates with any 1/4-20 tapped hole, nut, or channel nut. At 6 inches long it is a through-bolting length, so you will normally pair it with a nut and washer rather than a tapped hole.

Zinc plated carbon steel, which the JRM134 is, is a dry indoor fastener. The plating gives light corrosion protection for interior electrical work, panel and enclosure assembly, and similar protected locations. For wet, exterior, or washdown areas, go to a stainless machine screw of the same 1/4-20 x 6 in. size instead.

60,000 psi minimum, with the material running AISI 1006 to 1022 low carbon steel heat treated to Rockwell B70 to B100. That puts it in normal machine screw territory for mounting devices, panels, and enclosures. It is not a structural bolt, so do not substitute it where a drawing calls for a graded hex cap screw.

Metallics lists the JRM134 as compliant for both ARRA and Buy American, with country of origin China. Procurement officers on federally funded work should take the compliance flags as the vendor's statement and confirm against the specific clause in their contract, since the two programs treat origin differently.

They come in a jar of 100, and 100 count is the order minimum. That is the buying unit for MRO cribs and shops standardizing on one long machine screw; the jar weighs 6.77 lbs. Metallics notes other sizes and quantities are available by request.

Length is the whole point of the JRM134. A 6 inch 1/4-20 screw is what you reach for when you have to span a deep assembly, stacked spacers, insulation, or a built-out plaster ring, and the shorter stock in the drawer bottoms out. Because the thread is 1/4-20 the full length, you can run the nut wherever the stack actually ends and trim or leave the excess as needed.