Carriage bolts are fully threaded and also known as shaker screen bolts. They have a low profile head with a square neck that resists turning when nut is tightened or removed. Used for wood-towood and wood-to-metal applications. A square neck keeps them from turning when tightening a nut. A smooth, round head provides a finished look. Hot dipped galvanized (HDG) provides one of the highest degree of corrosion-resistance of all mechanically plated fasteners and is great for outdoor use. Grade 2 fasteners are used by contractors, designers, OEMs and maintenance staff in general applications and outdoor projects for non-critical joints and low stress applications. Tensile Strength: up to 5/8" - 64,000 p.s.i. (min) 3/4" diameter up to 55,000 p.s.i. (min). No radial bar marking on head. Made from low carbon steel.