Holo-krome 73018 Hex Socket Cap Screw 6-40 Unf 1/4 in

Product Description

The HOLO-KROME 73018 is a hex socket cap screw designed for applications requiring a compact, high-strength fastener with a recessed drive. Threaded 6-40 UNF and fully threaded along its 0.25-inch length under head, this screw is manufactured from alloy steel and finished with a black oxide coating that provides moderate corrosion resistance and a consistent dark appearance. The 7/64-inch hex drive accepts a standard hex key or Allen wrench. It conforms to ASME B18.3 and ASTM A574 standards, making it suitable for precision mechanical assemblies where dimensional consistency and tensile strength are critical requirements.

This fastener is used across a broad range of mechanical and industrial applications, including instrumentation panels, electrical enclosures, HVAC equipment assemblies, motor mounts, and general machinery. The fine 40-thread-per-inch UNF pitch provides greater thread engagement and improved resistance to loosening under vibration compared to coarse-thread equivalents, making it a preferred choice in tight-tolerance assemblies. Licensed tradespeople and mechanical contractors working on equipment fabrication or field repair will find this screw appropriate for light-duty to medium-duty fastening tasks where a low-profile socket head is needed.

Key Features

• 6-40 UNF fine-thread pitch for strong thread engagement and vibration resistance
• Fully threaded 0.25-inch length under head for maximum grip in thin-material applications
• Alloy steel construction meeting ASTM A574 tensile strength requirements
• Black oxide finish for mild corrosion resistance and reduced light reflection
• 7/64-inch hex socket drive compatible with standard hex keys
• Conforms to ASME B18.3 dimensional standards

Compatibility

Designed as a standard ASME B18.3 hex socket cap screw for use in any 6-40 UNF tapped hole requiring a 0.25-inch grip length and a 7/64-inch hex drive.

Installation Notes

Installation is performed using a 7/64-inch hex key or Allen wrench; ensure the drive tool is fully seated before applying torque to avoid rounding the socket. Power down or de-energize any equipment before fastening screws on or near electrical or HVAC components. Verify that mating threads in the tapped hole are clean and free of debris to ensure full thread engagement. This fastener is typically installed by mechanical contractors, HVAC technicians, or electricians during equipment assembly or field repair.