Holo-krome 77500 Hex Socket Cap Screw 3/8-24 Unf Alloy Steel

Product Description

The HOLO-KROME 77500 is a hex socket cap screw designed for high-strength fastening applications in mechanical assemblies, industrial equipment, and trade installations. It features a 3/8-24 UNF thread size with a 3.5-inch length under the head and is partially threaded for precise clamping in close-tolerance joints. The 5/16-inch hex drive socket head allows installation with a standard Allen wrench or hex key driver. Manufactured from alloy steel with a black oxide finish, this screw meets ASME B18.3 and ASTM A574 standards, making it suitable for demanding structural and mechanical fastening tasks.

This screw is used wherever a recessed-drive, high-strength fastener is required. Typical applications include machinery frames, HVAC equipment panels, pump and motor mounts, electrical enclosures, and general mechanical assemblies requiring a fine-thread fastener. The 3/8-24 UNF fine thread provides greater thread engagement per inch compared to coarse thread, making it well suited for thin-material joints and vibration-prone assemblies. Licensed trades and industrial maintenance technicians commonly specify this type of fastener for structural connections subject to torque and shear loads.

Key Features

• 3/8-24 UNF fine thread for strong thread engagement in close-tolerance applications
• 3.5-inch length under head with partial threading for precise clamping
• 5/16-inch hex socket drive compatible with standard Allen wrenches and hex key drivers
• Alloy steel construction meets ASTM A574 for high mechanical strength
• Black oxide finish provides mild corrosion resistance and reduces light reflection
• Conforms to ASME B18.3 dimensional standards

Compatibility

Designed as an OEM-style or replacement hex socket cap screw for mechanical assemblies, equipment frames, and industrial installations requiring a 3/8-24 UNF fine-thread partially threaded fastener with a 5/16-inch hex drive.

Installation Notes

Installation is typically performed by licensed mechanics, millwrights, HVAC technicians, or electricians using a calibrated torque wrench and the appropriate 5/16-inch hex key or Allen driver. De-energize and lock out all equipment before installing or removing fasteners in electrical or mechanical assemblies. Do not reuse fasteners that show signs of thread damage, galling, or deformation. Apply thread lubricant or anti-seize compound only if specified by the equipment manufacturer, as this affects torque-tension relationships.