12-28 x 4 1/2 Alloy Steel Socket Head Cap Screw is a socket head cap screw for buyers matching an exact thread and length to drawings, repair records, or stocked hardware. The size callout supports bill-of-material consistency when repair inventories cannot accept a substitute fastener. Applications often include manufacturing plants, power transmission, and fixture design, especially where counterbored or close-clearance mounting is required. 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: 12-28 Length: 4 1/2 in. Nominal Body Diameter: .215 in. Head Diameter: 0.337 in. min / 0.344 in. max Head Height: 0.211 in. min / 0.215 in. max Hex Key Size: 5/32 Drive Type: Internal hex socket Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.