Holo-krome 73120 Hex Socket Cap Screw 3/8-24 Unf Alloy Steel

Product Description

The HOLO-KROME 73120 is a hex socket cap screw built for high-strength fastening applications in mechanical, industrial, and trade service work. It features a 3/8-24 UNF thread size with a 3-inch length under head and partial threading along the shank. The drive is a 5/16-inch internal hex socket, accepting a standard Allen key or hex bit driver. Constructed from alloy steel with a black oxide finish, this screw delivers strong tensile performance while the coating provides moderate corrosion resistance in controlled environments. It conforms to ASME B18.3 and ASTM A574 fastener standards.

This screw is suited for use in precision mechanical assemblies, machinery, fixtures, and equipment requiring fine-thread fasteners. The 3/8-24 UNF fine thread pitch offers greater thread engagement per inch compared to coarse-thread equivalents, making it a good fit for applications with thin material sections or where vibration resistance and precise torque control are required. It is commonly installed by maintenance mechanics, millwrights, pipefitters, and equipment service technicians working on industrial or commercial systems.

Key Features

• 3/8-24 UNF fine thread for increased engagement and vibration resistance
• 3-inch length under head with partial threading for shank-bearing load applications
• 5/16-inch hex socket drive compatible with standard Allen keys and hex bit drivers
• Alloy steel construction meets ASTM A574 mechanical requirements
• Black oxide finish for surface protection in low-moisture environments
• Conforms to ASME B18.3 dimensional standards

Compatibility

Designed as a standard ASME B18.3 hex socket cap screw for use in any application requiring a 3/8-24 UNF partially threaded fastener with a 5/16-inch hex drive.

Installation Notes

Installation should be performed by qualified mechanical or trade personnel using a calibrated torque wrench and the appropriate 5/16-inch hex key or drive bit. De-energize and lock out all equipment before fastener service. Do not substitute a worn or incorrect-size hex key, as socket rounding will damage the drive recess and may compromise the assembly. Follow applicable equipment manufacturer torque specifications and relevant codes for the system being serviced.