Shop All Lag Bolts
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Available in various finishes for any application
Lag bolts feature a hex head and are designed to be driven with a wrench or hex driver. Lag screws are also commonly called lag bolts because they are significantly larger than most other screws. Essentially, it is just a very large wood screw with the threads extending to the top. They feature the sharp cutting threads of a wood screw or sheet metal screw and have a shoulder below the head (in longer lengths), however everything is scaled up in size for use in larger applications. These screws typically need a pre-drilled whole and are not recommended as self-tapping.
Lag bolts are used to lag together lumber framing, to lag machinery feet to wood floors, and other heavy carpentry applications. These fasteners are clearly "screws" when defined by the Machinery's Handbook distinction. The term "lag bolt" has been replaced by "lag screw" in the Machinery's Handbook.  However, in the minds of most tradesmen, they are "bolts", simply because they are large, with external-hex heads. In the United Kingdom, lag screws are known as coach screws.
Stainless Steel Lag Bolts
Hex lag screws in corrosion resistant 304 stainless steel. Lag screws, are basically "large wood screws". A typical lag bolt is 6 inches long, 3/8 diameter screw with coarse threads of a wood-screw or sheet-metal-screw thread form (but larger). Stainless Steel Coach Screws in this selection feature an external hex head. The materials are stainless steel for corrosion resistance. Grade 316 stainless steel lag screws are significantly more corrosion resistant than 304 and are ideal in harsh and saltwater environments.
Hot Dipped Galvanized Lag Screws
Hot dipped galvanized lag screws offer corrosion resistance to steel fasteners due to the molten zinc bath finishing process, creating a bonded alloy coating. The HDG process creates a tightly bonded alloy on the screws for superior corrosion resistance and harsh environment applications. HDG products must be used exclusively when applied, meaning that a plain zinc nut or stainless nut cannot be applied to an HDG bolt. HDG nuts are threaded slightly larger than other nuts to make room for the thickness of the galvanized coating.
Silicon Bronze Hex Lag Screws
Hex lag screws in corrosion resistant Silicon Bronze. A typical screw is 6 inches long with coarse threads of a wood-screw or sheet-metal-screw thread form (but larger). Silicon Bronze Lag Screws in this selection feature an external hex head. The materials are silicon bronze for corrosive, marine, and high heat environments.
Zinc Plated Steel Hex Lag Bolts
Lag screws with a zinc plated finish (CR+3) offer protection to the case-hardened fastener. They are available in standard SAE inch sizes in various lengths. While they have a protected layer of zinc, these screws are not as corrosion resistant as HDG and are not recommended for exterior use.
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