Coach screws are designed for metal to timber connections, or to join heavy timbers. Also known as lag bolts or lag screws, they have a square or hexagonal head engineered to be used with a wrench, spanner, or pliers. These screws come in a wide range of sizes, from the very small ones packed with furniture designed to be assembled by the consumer to extremely big ones used in large scale construction projects.Hex head lag wood screw
———A lag screw, or lag bolt, coach screw is a full-bodied bolt with square head or hex head, spaced threads, and a gimlet point. They are generally used to connect heavy lumber and other materials that bear an intense load.
———Zinc plated lag screws should be used for wood in non-corrosive environments, while hot dipped galvanized lag bolts can be used in corrosive environments, such as an outdoor deck.For even more protection, consider using stainless lag bolts.
———Lag bolts are designed for securely fastening heavy timbers (post and beams, timber railway trestles and bridges) to one another, or to fasten wood to masonry or concrete
———Lag bolts are usually used with an expanding insert called a lag in masonry or concrete walls, the lag manufactured with a hard metal jacket that bites into the sides of the drilled hole, and the inner metal in the lag being a softer alloy of lead, or zinc alloyed with soft iron.
———The coarse thread of a lag bolt and lag mesh and deform slightly making a secure near water tight anti-corroding mechanically strong fastening.

Specification