Metallics JBLS16G Bolts 5/16 x 4 Hx Lag Blt Galv (Jar 100)

Yes. The JBLS16G is a galvanized steel lag bolt intended for corrosive environments, which covers exterior framing, damp crawlspaces, and coastal or washdown areas. The base material is carbon steel in the AISI 1006 to 1022 range with the galvanized coating doing the corrosion work, so if the coating gets cut or ground off during install, that spot will rust.

The hex head measures 0.484 to 0.500 inch across the flats, so a 1/2 inch socket or wrench is the fit. Head dimensions follow ASME B18.2.1-1996, so standard impact sockets seat correctly. There is no drive recess, this is a wrench-driven head only.

It ships as a jar of 100 pieces, and 100 count is the order minimum. That is one jar per order increment, so a crew stocking a truck buys in hundreds rather than loose pieces. Other sizes and quantities can be arranged by request.

Full-bodied. The JBLS16G carries a full shank diameter of 0.298 to 0.324 inch under the head with spaced lag threads running to a gimlet point. A full body means the unthreaded portion fills the clearance hole and carries shear in the member being fastened, which is what you want for ledgers, hangers, and strut or conduit standoffs into wood.

The record flags it as both ARRA compliant and Buy American compliant, with country of origin listed as China. On federally funded work those two fields and the origin need to agree with your specific contract clause, so bring the manufacturer compliance letter to the submittal rather than relying on the catalog flag alone.

Minimum tensile strength is 60,000 psi with a hardness of Rockwell B70 to B100, on carbon steel per AISI 1006 to 1022. That is standard low-carbon lag screw territory, not a Grade 5 or Grade 8 structural bolt. For engineered structural connections where the drawing calls out a grade, specify a rated structural lag or through-bolt instead.

Not on their own. The JBLS16G is a wood lag with spaced threads and a gimlet point, meant to cut its own thread in timber. Into concrete or block you need a lead shield or lag expansion anchor sized for a 5/16 lag, and the bolt goes into the anchor rather than the substrate. Into steel, use a machine bolt or self-drilling screw instead.

Yes, use a flat washer under the head on wood. The hex head seats directly against the material and without a washer it crushes into softwood and loses clamp as the wood dries. Washers are not supplied with the jar of 100, so order galvanized flat washers for 5/16 bolts separately and match the coating so you do not set up dissimilar metal corrosion in an exterior location.