5/16-18 x 6 1/2 Alloy Steel Socket Head Cap Screw gives engineers an internal-hex fastener for mechanical joints where socket engagement and dimensional consistency matter. The exact 5/16-18 x 6 1/2 size helps buyers align the fastener with bill-of-material consistency. Common uses include manufacturing plants, industrial facilities, and industrial automation, where internal hex installation helps keep the joint accessible. Verified head dimensions and hex key size help engineering departments check fit before ordering. The combination of product name, size, material, and verified head data improves search clarity for engineers and buyers. Technical Highlights Material: Alloy Steel Thread: 5/16-18 Length: 6 1/2 in. Nominal Body Diameter: .312 in. Head Diameter: 0.457 in. min / 0.469 in. max Head Height: 0.306 in. min / 0.312 in. max Hex Key Size: 1/4 Drive Type: Internal hex socket Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.