4-40 x 1/8 Brass Cup Point Socket Set Screw is a Brass Cup Point Socket Set Screw used when a headless internal-hex fastener is specified for retaining or positioning a component.

It is commonly used in shaft collars, hubs, and control components, where a headless fastener secures a part without external head clearance. The internal hex drive allows socket-wrench access from the threaded hole, which is useful when surrounding components leave little room for external wrenching.

Review the 4-40 thread, 1/8 in. length, socket size, cup point diameter, mating surface, and material requirements before specifying the item. Confirm that point contact, brass material, and service conditions fit the application. Brass is often selected for nonferrous construction, electrical conductivity, general corrosion resistance, and distinctive appearance. The cup point creates rim-focused contact that may help resist relative movement when the screw, mating material, and installation conditions are appropriate. Cold Headers supports exact-size sourcing for brass socket set screws, including uncommon lengths and replacement requirements.

Technical Highlights

• Material: Brass
• Thread Size: 4-40
• Length: 1/8 in.
• Point Style: Cup Point
• Nominal Screw Diameter: 0.112 in.
• Hex Socket Size: 0.050 in.
• Cup Point Diameter: 0.051-0.061 in.
• Drive Type: Internal Hex

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