Metallics JHTB39 Bolts 5/16-18 X 1 Hx Tap Blt St-zn (Jar 100)

The JHTB39 is a 5/16-18 hex tap bolt, so 18 threads per inch, right hand thread, 1 inch long. It follows the IFI-199 (2014) thread standard, which means it mates with standard 5/16-18 UNC nuts, strut nuts, and tapped holes.

No. The JHTB39 is not Buy American compliant and not ARRA compliant, with country of origin listed as multiple. On a federally funded project with domestic sourcing language, you will need a domestically produced fastener instead.

A hex tap bolt is threaded the full length of the shank instead of having an unthreaded shoulder. That is why the JHTB39 is listed for complete thread engagement applications: with 1 inch of thread on a 1 inch bolt, you get thread biting all the way into a tapped hole or nut, which matters on thin channel, strut, and sheet metal where a partially threaded bolt would bottom its shoulder before clamping. If you are through-bolting a thick stack and want a shoulder in the shear plane, a partially threaded hex cap screw is the better choice.

Head width across the flats measures 0.484 to 0.500 inch, so a 1/2 inch wrench or socket is the one to grab. Width across the corners runs 0.552 to 0.577 inch, useful if you are figuring clearance in a tight channel or box.

The JHTB39 is zinc plated steel. Zinc plating handles indoor, dry, and lightly damp conditions, but it is not a stainless part, so for wet exterior, coastal, or washdown work step up to the 18-8 stainless version of the hex tap bolt line rather than using the zinc.

They come in a jar of 100. Order minimum is one jar, 100 pieces, so you cannot buy these by the individual bolt. Other sizes and quantities can be requested.

Head height runs 0.195 to 0.235 inch, so plan on roughly a quarter inch of stand-off above the mounting surface. The head is a standard hex, not a flange or washer head, so add a washer thickness if you are using one.