Metallics JSBH551 Bolts 1/4-20 X 4 Hxbt SS (Jar 100)

The JSBH551 is a 1/4-20 hex bolt, 4 inches long. Thread count is 20 threads per inch, and the shank measures 0.2450 to 0.2500 inch outside diameter, so it takes a standard 1/4-20 nut or tapped hole. Hex head width across flats runs 0.428 to 0.438 inch, which a 7/16 inch wrench or socket drives.

The JSBH551 is 316 stainless steel. The added molybdenum in 316 gives better corrosion resistance than 18-8 and holds strength better at elevated temperature, which is why it gets specified for coastal, wash-down, pool chemical, and other wet or chloride-exposed work where 18-8 pits.

No. The JSBH551 is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. For a federally funded project with domestic sourcing language in the spec, you need a domestically produced fastener instead.

Tensile strength is 100,000 to 150,000 psi minimum with a 65,000 psi minimum yield, and hardness is Rockwell B95 to C32. That is typical austenitic stainless territory: strong enough for structural attachment of boxes, strut, racks, and equipment, but it is not a substitute where a drawing calls out a Grade 8 or alloy-steel socket cap screw. Stainless also galls, so run it with an anti-seize or a stainless nut of a different alloy if you are torquing hard.

It ships as a jar of 100 pieces, and 100 count is the order minimum. Handy if you are stocking a service van or an MRO crib rather than pulling from a bulk box. Other sizes and quantities can be had by request.

At 4 inches of bolt length you have room for stacked material plus washers and nut, which covers strut-to-bracket, through-bolting a backplate, or picking up a thick wood or steel member. Head height adds a small amount above the surface, and the hex head measures 0.428 to 0.438 inch across flats, so check clearance where the head sits against a channel lip or inside a shallow box. For thin stack-ups the extra length just leaves thread hanging past the nut, so a shorter bolt is the cleaner choice there.

A hex head like the JSBH551 drives with an open-end, box, or socket wrench, which is what you want in a panel or overhead where you cannot get a hex key straight on the fastener. Socket cap screws are the better pick when the head has to sit in a counterbore or in a tight recess with no wrench swing. The JSBH551 is the hex head version in the SBHC and JSBHC family.

Stainless against aluminum or hot-dip galvanized steel in a wet location sets up galvanic corrosion, with the aluminum or zinc as the sacrificial side. The JSBH551 is 316 stainless, so for outdoor or wash-down assemblies on aluminum, isolate with a nylon or neoprene washer or seal the joint. In dry interior work it is a non-issue.