Metallics JG5HTB20 Bolts 5/16-18 X 4 G5 Hx Tap Blt St-zn (Jar 100)

Yes. A hex tap bolt is threaded all the way to the head, which is what separates it from a standard hex cap screw with a plain shoulder. The JG5HTB20 is 5/16-18 by 4 inches, right-hand thread at 18 threads per inch, so you can engage a nut or tapped hole anywhere along the shank. Useful when your grip length varies from one piece of machinery to the next.

That is the job these are built for. Grade 5 means medium carbon steel, heat treated, with 105,000 psi minimum tensile and a Rockwell C19-30 hardness. Metallics lists motor mounting to machinery as the primary use, along with automotive and truck repair. For higher clamp loads than Grade 5 will carry you would step up to a Grade 8 fastener instead.

The head measures 0.489 to 0.500 inch across the flats, so a 1/2 inch wrench or socket is the fit. Head height runs 13/64 inch, with about 0.14 inch of wrenching height, so you need roughly that much clear vertical access for the socket to seat on the flats, not just the chamfer.

Zinc plating over steel gives you basic corrosion protection, fine for indoor mechanical rooms, equipment rooms and covered work. For continuous wet exposure, coastal air or washdown areas, zinc plating will eventually sacrifice and rust through, so a stainless fastener is the better call there. The JG5HTB20 is zinc plated carbon steel.

It ships as a jar of 100, and 100 count is the order minimum, so the jar is the smallest unit. Metallics does offer other sizes and quantities in the G5HTB and JG5HTB series by request if 4 inch or a 100 pack is not what the job needs.

Threads and head dimensions follow ASME B18.2.1-2012, and the material is in the AISI 1008-1026 range. That means it interchanges dimensionally with any other B18.2.1 5/16-18 hex tap bolt, so a 1/2 inch head and standard nut or tapped 5/16-18 hole will take it regardless of who made the bolt you are replacing.

Metallics lists this hex tap bolt as compliant for both ARRA and Buy American purposes. Country of origin is China. If your contract language requires domestic melt and manufacture rather than the compliance flag, verify against the clause in your contract before you commit the lot.

Outside diameter measures 0.3065 to 0.3125 inch. That is a nominal 5/16, so a 5/16 clearance hole will be a tight slip fit and most installers open it to 11/32 or 3/8 inch for through-bolting so you can line up the hole pattern. For a tapped blind hole, the thread is 5/16-18 right hand.

The jar contains bolts only, 100 of them. Nuts, flat washers and lock washers are separate line items, so size them to 5/16-18 right hand thread and match the plating if you want to avoid galvanic issues, meaning zinc plated nuts with these zinc plated bolts.