Metallics JHTB81 Bolts 1/2-13 X 3/4 Hx Tap Blt St-zn (Jar 50), 100 Pack

The JHTB81 is a 1/2-13 hex tap bolt, meaning a 1/2 inch diameter with 13 threads per inch, right hand thread, in a 3/4 inch length. The 13 TPI is the standard UNC coarse pitch for 1/2 inch, so it mates with standard 1/2-13 nuts, tapped channel and threaded inserts.

The JHTB81 is carbon steel with a zinc finish, which is a plating for indoor and protected use. It handles normal indoor humidity fine, but in wet, exterior, coastal or chemically aggressive locations the plating wears and the steel rusts. For those openings step up to a stainless hex tap bolt; Metallics builds the same tap bolt in 18-8 stainless under the JSHTB designation within the same HTB, JHTB and JSHTB series.

Minimum tensile strength is 60,000 psi, with a hardness range of Rockwell B69 to B100. That puts it in the low carbon, general purpose class, which is what you want for hanging conduit, strut, boxes and equipment supports. It is not a high strength structural bolt, so if a drawing calls out a Grade 5 or Grade 8 fastener for a load bearing connection, specify that instead.

No. The JHTB81 hex tap bolt is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. If your contract carries a domestic sourcing clause, this part will not pass the submittal and you need a domestically produced fastener instead.

A hex tap bolt is threaded the full length of the shank rather than having an unthreaded shoulder, which is why Metallics lists the JHTB81 for complete thread engagement applications. Use it when you need threads all the way into a tapped hole, strut nut or insert, or when the grip length is short, as it is here at 3/4 inch. If you are clamping a thick stack and want the shear plane on a plain shank, a partially threaded hex cap screw is the better choice.

Head is a standard hex with an across flats width of 0.725 to 0.750 inch, so a 3/4 inch socket or open end wrench is the right tool. Handy to know when you are working in a crowded strut run and need to confirm clearance before you buy.

These ship in jars of 50 pieces, and the order minimum is 50 each, so one jar is the smallest buy. Jar packaging keeps the count honest on a service van or a stockroom shelf instead of loose bolts in a bin.

Threads are made to IFI-199 (2014). If your spec sheet calls out that standard for inch series threads, the 1/2-13 JHTB81 meets it, and the thread form will interchange with other IFI-199 inch hardware on the job.

Metallics lists this one for the electrical, plumbing, heating and air conditioning trades. In practice it is the short fully threaded bolt you reach for on strut and channel nut connections, hanger and bracket attachment, pipe clamp and support assembly, and equipment mounting where the tapped hole is shallow.