Metallics JBLS4G Bolts 1/4 X 3 Hx Lag Blt Galv (Jar 100)

That is what the galvanized finish on the Metallics JBLS4G is for. The steel bolt carries a galvanized coating and the series is called out for use in corrosive environments, so exterior framing, damp crawl spaces, and coastal or chemical-exposure areas are the intended use. For dry interior work a plain zinc lag does the same mechanical job, but it won't hold up outside.

Size the pilot to the shank, not the thread. The JBLS4G measures 0.237 to 0.260 inch across the outside diameter with 10 threads per inch and a gimlet point. In solid wood a 3/16 inch pilot in softwood and 7/32 inch in hardwood is the normal practice for a 1/4 inch lag; the gimlet point lets it start without a pilot in soft material, but pre-drilling prevents splitting near edges and end grain.

The JBLS4G is made from AISI 1006 to 1022 low carbon steel with a minimum tensile strength of 60,000 psi and a hardness of Rockwell B70 to B100. That is standard lag screw material, suitable for attaching ledgers, brackets, conduit supports and strut to wood framing. It is not a heat-treated high strength bolt, so don't substitute it where a Grade 5 or Grade 8 machine bolt is specified on the drawing.

No. The JBLS4G has spaced threads and a gimlet point, which is wood screw geometry, and it is meant to bite into timber. For concrete, block or brick you need a concrete screw anchor or a sleeve or wedge anchor sized to the fixture, or a lead or plastic shield that a lag can thread into. Driving a lag straight into masonry will not hold.

The hex head measures 0.425 to 0.438 inch across the flats, which is a 7/16 inch socket or wrench. Drive it with a socket and ratchet or an impact driver with a 7/16 hex socket, not a screwdriver bit.

These ship in a jar of 100 pieces, and 100 count is the order minimum. The jar keeps them contained on a service truck or in a stockroom bin rather than loose in a bag. Other sizes and quantities in the BLS and JBLS series can be had by request.

The JBLS4G is flagged compliant for both ARRA and Buy American in the manufacturer's data, with country of origin listed as China. If your specification requires domestic melt and manufacture rather than the broader compliance flag, confirm the exact clause your project is written to before you submit.

Use one anywhere the head bears directly on wood or on a thin bracket. The hex head on the JBLS4G is 0.425 to 0.438 inch across the flats, which is a small bearing surface and will crush into softwood as you torque it. A flat washer spreads that load and lets you pull the joint tight without sinking the head. Washers are not supplied with the jar.