4-40 x 5/8 Brass Button Head Socket Cap Screw helps designers combine a compact rounded head profile with material properties useful for electrical and instrumentation work. The broader bearing surface can be helpful on covers, light brackets, and equipment panels where the head remains visible. The material supports clean machining and a finished look for commercial hardware, instruments, and visible assemblies.

Appropriate uses include laboratory equipment and commercial fixtures, where non-ferrous construction and a clean exposed head are often preferred over plain steel hardware. It can also fit laboratory equipment and commercial fixtures, where non-ferrous construction and a clean exposed head are often preferred over plain steel hardware. The internal hex drive supports socket-key installation in compact equipment without relying on an external wrenching surface.

For the 4-40 thread and 5/8 in. length, the reference head diameter is 0.201-0.213 in. and the head height is 0.051-0.059 in. Use the verified dimensions below when checking head projection, socket access, and replacement fit.

Technical Highlights

• Material: Brass
• Thread Size: 4-40
• Length: 5/8 in.
• Nominal Body Diameter: #4 (.112 in.)
• Head Diameter: 0.201-0.213 in.
• Head Height: 0.051-0.059 in.
• Hex-Key Size: 1/16 in.
• Drive Type: Internal Hex

Reference dimensions may vary slightly by manufacturer.