7/8-9 x 4 Alloy Steel Socket Head Cap Screw is commonly used where an Allen-style socket drive is preferred over external-wrench hardware in confined equipment layouts. The size callout supports service work where the exact thread and length are already defined when socket-drive service locations cannot accept a substitute fastener. Industrial buyers may specify it for packaging machinery, engineering departments, and production lines where head geometry and drive access need to be predictable. Internal hex drive access helps installation in compact assemblies, guards, housings, and fixture plates. This exact size supports industrial hardware, repair, and production requirements. Technical Highlights Material: Alloy Steel Thread: 7/8-9 Length: 4 in. Nominal Body Diameter: .875 in. Head Diameter: 1.293 in. min / 1.312 in. max Head Height: 0.864 in. min / 0.875 in. max Hex Key Size: 3/4 Drive Type: Internal hex socket Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.