Hex head cap screws are used to secure an object within or against another object. They have tighter tolerances, has a chamfered end and a washer face under the bolt head. The main difference between a hex cap screw and hex bolt is a hex bolt does not have a washer face under the bolt head. Hot dipped galvanized (HDG) provides one of the highest degrees of corrosion-resistance of all mechanically plated fasteners. Used in all exterior applications where prolonged exposure to the elements are present. Ideal for marine applications such as docks and piers as well as landscaping projects including decks, fences, retaining walls, and more. Grade 2: fasteners are used by contractors, designers, OEMs and maintenance staff in general applications 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.