Metallics JG5HTB108 Bolts 3/8-16 x 6 G5 Hx Tap Blt St-zn (Jar 50)

Yes. The JG5HTB108 is a hex tap bolt, which means the 6 inch length is fully threaded rather than having a plain shoulder under the head. That is what separates a tap bolt from a standard hex cap screw, and it is why these are used for mounting motors to machinery and in automotive and truck repair, where the fastener often threads directly into a tapped hole rather than taking a nut.

Tight. Body outside diameter runs 0.3690 to 0.3750 inch, which is the full 3/8 inch nominal, so a hole drilled at exactly 3/8 leaves no clearance. For through-bolting, drill 13/32 or 7/16 inch. The 0.3690 to 0.3750 figure is the thread major diameter, so a tapped hole should be cut for 3/8-16 right hand thread.

Grade 5 means medium carbon steel that has been heat treated, and this one carries a minimum 105,000 psi tensile and 105,000 psi yield with a hardness of Rockwell C19-30. An unmarked Grade 2 bolt is not heat treated and runs well below that, so it should not be swapped in on a motor mount or any clamped load that was specified Grade 5. Grade 5 heads carry three radial lines as the identifying mark.

The finish is zinc plating over steel, which handles indoor and sheltered conditions and incidental moisture. It is not a marine or continuously wet duty coating, and zinc will eventually sacrifice and rust in standing water or salt spray. For a washdown area, exterior rooftop equipment, or coastal work, specify a stainless or hot dip galvanized fastener instead.

The JG5HTB108 is flagged compliant for both ARRA and Buy American in Metallics' product data, with country of origin China. On a federally funded job where the specification demands domestically melted and manufactured fasteners, treat the origin as the governing fact and get the submittal reviewed before you install 50 of them.

Thread and head geometry follow ASME B18.2.1-2012, the standard for inch square and hex bolts and screws, with the steel to AISI 1008-1026. Because the thread is standard 3/8-16 right hand, any off the shelf 3/8-16 hex nut, lock nut, or tapped 3/8-16 hole will mate with it. Match the nut grade to the bolt (a Grade 5 nut) so the joint is not limited by the nut.

You can, but a 6 inch fully threaded bolt in a shallow joint leaves a long unsupported stub that is easy to bend and gets in the way of adjacent equipment. Pick the length so the bolt protrudes a few threads past the nut or bottoms properly in the tapped hole. The G5HTB and JG5HTB hex tap bolts come in other lengths by request if 6 inches is longer than the grip you have.