Metallics JBLS39 Bolts 1/4 X 1-3/4 Hx Lag Blt St-zn (Jar 100 )

No. The JBLS39 is a zinc-plated steel lag bolt specified for use in wood in non-corrosive environments. Zinc plating is not the right coating for weather exposure or for the chemistry in modern pressure-treated lumber, where a hot-dip galvanized or stainless lag is the correct choice. Keep this one on interior, dry framing: hanging strut, mounting panels, backing boxes to studs.

Yes, drill a pilot in anything other than soft, thin stock. The JBLS39 has a gimlet point so it starts itself, but at a 0.237 to 0.260 inch shank diameter with 10 threads per inch it displaces enough wood to split a stud edge or a joist end if you drive it dry. Standard practice is a pilot sized to the root of the thread in the member being threaded, with the top piece drilled clear for the unthreaded shank. Threads are right hand, so drive clockwise.

The JBLS39 is a full-bodied lag with a 60,000 psi minimum tensile strength and a hardness of Rockwell B70 to B100, made from low carbon steel in the AISI 1006 to 1022 range. That is ordinary commercial-grade lag screw material, which is what strut, unistrut backing, panel mounting and conduit hangers in wood are normally fastened with. Metallics lists it for the electrical, plumbing, heating and air conditioning trades. Holding capacity in a wood connection comes from thread embedment, and at 1-3/4 inches overall you have limited penetration once you subtract the thickness of whatever you are fastening through.

No. The JBLS39 is not Buy American compliant and is not ARRA compliant, and the country of origin is listed as multiple. If your spec carries a domestic sourcing clause, this jar will not satisfy it and you need a domestically produced lag.

These ship 100 to the jar, and the jar is the order minimum, so 100 pieces is the smallest buy. Metallics does make other sizes and quantities in the BLS and JBLS lag bolt series available on request if 1/4 x 1-3/4 or a 100 count does not suit the job.

Yes, it is made to ASME B18.2.1-1996, the standard that governs square and hex bolt and screw dimensions. That matters when a submittal or a drawing calls out a dimensional standard rather than a part number, and it means head and thread geometry will match any other lag built to the same spec.

A lag threads directly into wood and needs no nut on the back side, which is why it suits framing, blocking and plywood backing where you can only reach one face. It is the wrong part for masonry or concrete, where you need a screw anchor or a wedge anchor instead, and the wrong part where you can access both sides of a steel member and should use a through bolt with a nut. The JBLS39 is specified for wood in non-corrosive environments.