4-40 x 1 1/2 Brass Button Head Socket Cap Screw gives buyers a defined brass button-head fastener for equipment where appearance, conductivity, and serviceable socket access matter. The internal hex drive keeps the installation tool inside the head, which is useful when external wrench clearance is limited. Brass is appropriate for many low-load mechanical assemblies where corrosion resistance in general service, appearance, and electrical behavior matter.

Appropriate uses include precision instruments and panel hardware, where the broad bearing surface can help seat the head cleanly on covers or brackets. It can also fit precision instruments and panel hardware, where the broad bearing surface can help seat the head cleanly on covers or brackets. The internal hex drive supports socket-key installation in compact equipment without relying on an external wrenching surface.

For the 4-40 thread and 1 1/2 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: 1 1/2 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.