Metallics JBLS12SS50 Bolts 5/16 X 2 Hx Lag Blt SS (Jar 50)

It's a 5/16 inch diameter by 2 inch long hex head lag bolt in 18-8 stainless steel, packed 50 to a jar. Measured shank diameter runs 0.298 to 0.324 inch and the thread is 9 threads per inch, which is standard spaced lag threading rather than a machine thread. Order minimum is 50 count, so a jar is the base unit.

Yes. These are 18-8 stainless, and Metallics states they have superior corrosion resistance to galvanized steel bolts. That makes them the choice for exterior mounting, coastal or damp environments, and anywhere a galvanized coating would eventually be scraped or weathered through. One caution for MRO crews: mixing stainless fasteners with galvanized or plain steel brackets in wet service can drive galvanic corrosion of the steel part, so keep the materials consistent where you can.

Metallics lists the JBLS12SS50 as Buy American compliant and ARRA compliant. Country of origin is China. If your specification reads Buy American under ARRA, that compliance flag is what your submittal package needs, and the origin is disclosed so there are no surprises at closeout.

The JBLS12SS50 has a gimlet point, so it will start itself in soft wood, but a pilot hole is still the right practice at 5/16 inch. Stainless is softer than hardened carbon steel (hardness here is Rockwell B95 to C32), and galling or snapping the head is a real risk if you drive it dry into dense lumber. Drill the pilot and the shank diameter of 0.298 to 0.324 inch gives you your reference.

They are built to ASME B18.2.1-1996, the dimensional standard for square and hex bolts and lag screws. A 5/16 x 2 hex lag made to that standard will drop into the same hole and take the same 1/2 inch socket regardless of who made it, so substituting into an existing run of 5/16 lags is not a problem on geometry. Material is the thing to match: these are 18-8 stainless, not plated carbon steel.

Tensile strength is approximately 100,000 to 125,000 psi minimum with hardness at Rockwell B95 to C32. For a full-bodied 5/16 lag that's typical 18-8 stainless territory and plenty for strapping conduit, mounting boxes, strut, and light equipment to wood framing. Real holding power on a lag is governed by thread engagement in the substrate, not the bolt, so at 2 inches of length plan on landing solid wood, not just sheathing.

Washers are not part of the jar of 50. The spec does list a washer OD reference of 0.125 in. for the series, but plan on sourcing flat washers separately if your detail calls for them. With a 5/16 lag into wood, a flat washer under the hex head is worth having so the head does not crush into the material as you torque it.

The JBLS12SS50 is the 5/16 x 2 inch size in a 50 count jar, and it is part of the Metallics BLS and JBLS lag bolt series. Metallics notes that other sizes and quantities in the series are available by request, so if you need a longer lag for thicker framing or bulk packs instead of jars, ask rather than assuming the jar is the only option.

The packed jar weighs 2.12 lbs. Jar dimensions are listed at 3 inches length, 3 inches width, 4.57 inches height, which is useful if you are stocking a truck bin or a shop shelf by the case.