6-40 x 5/8 Alloy Steel Socket Head Cap Screw provides a strength-focused alloy steel socket cap screw option for mechanical assemblies requiring this exact size. For actuated equipment, the 6-40 thread and 5/8 in. length help confirm the correct socket cap screw before installation. Common uses include machine tools, processing equipment, and robotics, 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: 6-40 Length: 5/8 in. Nominal Body Diameter: .138 in. Head Diameter: 0.218 in. min / 0.226 in. max Head Height: 0.134 in. min / 0.138 in. max Hex Key Size: 7/64 Drive Type: Internal hex socket Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.