6-40 x 3/8 Alloy Steel Button Head Socket Cap Screw supports compact fastening in assemblies where a cylindrical socket head would project farther from the surface. The alloy steel construction is selected for production equipment where a lower-profile head is preferred on exposed fastening points.

Designers often specify it for brackets, fixtures, and tooling assemblies where the broad head distributes contact over a wider seating area. It can also serve brackets, fixtures, and tooling assemblies when the broad head distributes contact over a wider seating area. Selection is usually driven by head shape, socket access, and exposed-surface requirements rather than by the geometry of a standard socket head cap screw.

For drawings using the 6-40 thread and 3/8 in. length, the reference head diameter is 0.250-0.262 in. and the head height is 0.063-0.073 in. The nominal body diameter and hex-key information below support fit checks, tool access planning, and replacement verification.

Technical Highlights

• Material: Alloy Steel
• Thread Size: 6-40
• Length: 3/8 in.
• Nominal Body Diameter: #6 (.138 in.)
• Head Diameter: 0.250-0.262 in.
• Head Height: 0.063-0.073 in.
• Hex-Key Size: 5/64 in.
• 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.