3/8-16 x 3 1/2 Alloy Steel Socket Head Cap Screw helps maintenance and engineering teams source an alloy steel internal-hex screw with verified head-size data. The 3/8-16 thread and 3 1/2 in. length support bill-of-material consistency in counterbored mounting points. Common uses include tooling, power transmission, and machine tools, where internal hex installation helps keep the joint accessible. Internal hex drive access helps installation in compact assemblies, guards, housings, and fixture plates. This keeps the listing focused on the fastener geometry rather than broad catalog language. Technical Highlights Material: Alloy Steel Thread: 3/8-16 Length: 3 1/2 in. Nominal Body Diameter: .375 in. Head Diameter: 0.550 in. min / 0.562 in. max Head Height: 0.368 in. min / 0.375 in. max Hex Key Size: 5/16 Drive Type: Internal hex socket Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.