Holo-krome 77482 Hex Socket Cap Screw 1/4-28 Unf 4 in

Product Description

The HOLO-KROME 77482 is a hex socket cap screw designed for applications requiring a secure, high-strength threaded fastener with a recessed drive. Built to 1/4-28 UNF thread specification, it carries a 4-inch length under head and is driven by a 3/16-inch hex key. Constructed from alloy steel and finished with a black oxide coating, this screw offers good corrosion resistance in controlled environments and meets ASME B18.3 and ASTM A574 standards. It is partially threaded and suited for use wherever a precision-fit socket cap screw is called for in mechanical assemblies.

This screw is commonly used in industrial equipment, mechanical assemblies, jigs, fixtures, and maintenance applications across HVAC, plumbing, electrical, and general mechanical trades. The 1/4-28 UNF fine thread pitch provides strong clamping force and resistance to loosening under vibration, making it a practical choice for equipment panels, brackets, and structural fastening tasks in trade environments.

Key Features

• 1/4-28 UNF fine thread for strong clamping and vibration resistance
• 4-inch length under head with partial threading
• 3/16-inch hex socket drive for standard Allen key installation
• Alloy steel construction meeting ASTM A574 requirements
• Black oxide finish for moderate corrosion resistance in dry or oiled environments
• Compliant with ASME B18.3 dimensional standards

Compatibility

Designed as a standard 1/4-28 UNF hex socket cap screw per ASME B18.3, suitable for use in any application requiring this thread size, length, and drive configuration.

Installation Notes

Installation requires a 3/16-inch hex key or Allen driver. Ensure the mating threaded hole is clean and free of debris before fastening. Apply appropriate thread lubricant or anti-seize if required by the application. Do not exceed the rated torque specification for 1/4-28 alloy steel fasteners as defined by the applicable engineering standard for the assembly.