Metallics JG8HC5 Bolts 1/4-20 x 2-1/2 G8 HXBT St-zn (Jar 50)

It's 1/4-20 UNC: 20 threads per inch on a shank measuring 0.2450 to 0.2500 inch outside diameter. Any standard 1/4-20 coarse nut or 1/4-20 tapped hole will take it. Usable length is 2-1/2 inches, so subtract the thickness of what you are clamping to size your nut and washer stack.

Strength. The JG8HC5 is a Grade 8 cap screw rated 150,000 psi minimum tensile and 130,000 psi minimum yield, where a Grade 5 tops out lower. If you are hanging heavy equipment, bolting motor bases, or working on fleet and automotive gear where the joint sees vibration and high clamp loads, Grade 8 is the one that holds. For light sheet-metal and general fixture work, a Grade 5 is usually enough and easier on the tool.

No. The JG8HC5 is not Buy American compliant and not ARRA compliant, and country of origin is listed as multiple. If your contract carries a domestic-content clause, these won't satisfy it and you'll need a domestically sourced Grade 8 hex cap screw.

The JG8HC5 is medium carbon steel with a zinc finish, which handles indoor and normally dry or occasionally damp conditions. It is not stainless and not hot-dip galvanized, so for direct weather exposure, wash-down areas, coastal sites, or buried work you want a stainless or hot-dip galvanized fastener instead. Zinc on plated Grade 8 also carries a hydrogen-embrittlement consideration, so don't substitute it into a critical structural joint that specifies something else.

They ship as a jar of 50, and 50 each is the order minimum, so the jar is the smallest buy. No loose counts. Metallics does make other sizes and quantities in the G8HC and JG8HC series on request if 2-1/2 inch isn't the length you need.

Steel in the AISI 1021 to 1045 range, heat-treated to Rockwell C33-39. At that hardness they resist thread galling and stripping under high torque, but they are not meant to be drilled, cut, or welded, heat destroys the temper that gives you the Grade 8 rating. Order the length you need rather than trimming these down.

Both. Metallics lists field application as the electrical, plumbing, heating and air conditioning industries, and the same Grade 8 cap screw is used in automotive and fleet work where Grade 5 strength isn't enough. For an MRO crib it's a reasonable standardization item across trades at the 1/4-20 size.