12-28 x 5/16 Alloy Steel Button Head Socket Cap Screw is commonly specified when designers need internal-hex access with a broad, finished head profile. The alloy steel construction supports manufacturing equipment where a smooth button head and socket engagement are required.

It is commonly used on robotics and packaging machinery where internal hex drive access supports repeatable assembly work in tight spaces. It is also suited to precision assemblies and repair work when buyers can match the listed thread and length to drawings or service records. Unlike a standard socket head cap screw, the button head emphasizes a lower rounded profile and broader exposed head for applications that benefit from that geometry.

For assemblies specified with 12-28 thread and 5/16 in. length, the reference head diameter is 0.383-0.413 in. and the head height is 0.104-0.117 in. The nominal body diameter and hex-key information below help maintenance and purchasing teams verify fit and tool access.

Technical Highlights

• Material: Alloy Steel
• Thread Size: 12-28
• Length: 5/16 in.
• Nominal Body Diameter: #12 (.215 in.)
• Head Diameter: 0.383-0.413 in.
• Head Height: 0.104-0.117 in.
• Hex-Key Size: Hex-key size may be 1/8 in. or 5/32 in., depending on manufacturer.
• Drive Type: Internal Hex

Reference dimensions may vary slightly by manufacturer.

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.