Holo-krome 64058 Button Socket Cap Screw 5/16-18

Product Description

The HOLO-KROME 64058 is a button head socket cap screw designed for mechanical assemblies requiring a low-profile fastening solution with high tensile strength. It features a 5/16-18 UNC thread and a 3/4-inch length under head, fully threaded with a Class 3A thread fit for close-tolerance applications. The alloy steel construction is finished in black oxide for corrosion resistance in indoor and mildly corrosive environments. A 3/16-inch hex socket drive provides secure torque transfer. This fastener meets ANSI/ASME B18.3 and ASTM F835 standards and is commonly installed by machinists, millwrights, and field service technicians working on equipment, panels, and structural components.

This screw is suited for use in light machinery, enclosures, brackets, and equipment frames where a flush or near-flush fastener profile is preferred over a standard hex cap screw. The button head geometry distributes clamping load over a wider bearing surface, making it a practical choice for softer base materials or thin-stock assemblies. It is appropriate for both OEM manufacturing and field maintenance applications across industrial, HVAC, electrical, and general mechanical trades.

Key Features

• Button head profile provides low-clearance fastening with wide bearing surface
• Alloy steel construction with 38 HRC hardness for high-strength applications
• Black oxide finish for mild corrosion resistance and reduced light reflection
• 5/16-18 UNC Class 3A thread fit for precise, close-tolerance engagement
• Fully threaded shank along 3/4-inch length under head
• Meets ANSI/ASME B18.3 and ASTM F835 fastener standards

Compatibility

Designed as a standard ANSI/ASME B18.3 button socket cap screw suitable for general mechanical assemblies, equipment frames, enclosures, and machinery requiring a 5/16-18 UNC fully threaded fastener with a hex socket drive.

Installation Notes

Installation requires a 3/16-inch hex key or socket bit driver. Verify that mating threads are clean and free of debris before driving. Apply thread lubricant or thread-locking compound as required by the application and applicable mechanical codes. De-energize or lock out any equipment before fastener service to comply with applicable OSHA lockout/tagout procedures.