5/8-18 x 5 Alloy Steel Socket Head Cap Screw is specified when a machine assembly needs a high-strength alloy steel socket screw with predictable head and drive geometry. With a 5/8-18 thread and 5 in. length, it fits repair inventories where size interchangeability matters. Common uses include production lines, power transmission, and industrial facilities, where internal hex installation helps keep the joint accessible. Alloy steel supports strength-focused fastening where clamp load and repeatable assembly are important. This keeps the listing focused on the fastener geometry rather than broad catalog language. Technical Highlights Material: Alloy Steel Thread: 5/8-18 Length: 5 in. Nominal Body Diameter: .625 in. Head Diameter: 0.921 in. min / 0.938 in. max Head Height: 0.616 in. min / 0.625 in. max Hex Key Size: 1/2 Drive Type: Internal hex socket Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.