Holo-krome 79040 Hex Socket Cap Screw 1/4-28 Unf Ss 18-8

Product Description

The HOLO-KROME 79040 is a hex socket cap screw designed for precision fastening in mechanical, plumbing, and industrial assemblies. It features a 1/4-28 UNF thread - a fine-pitch thread pattern suited for applications requiring tighter thread engagement and vibration resistance. The screw is fully threaded along its 1-inch length under head and accepts a 3/16-inch hex drive. Constructed from 18-8 stainless steel with a bright uncoated finish, it delivers solid corrosion resistance in moderate-exposure environments. This fastener meets ASME B18.3, ASTM A574, and ASTM F837 standards, making it appropriate for specification-driven work where dimensional and material compliance is required.

This screw is commonly used in equipment assemblies, valve bodies, pump housings, panel mounting, and other mechanical sub-assemblies where a fine-thread socket cap fastener is specified. The 1/4-28 UNF thread is a standard fine-pitch size found across HVAC, plumbing, and light industrial equipment. The 18-8 stainless steel construction makes it suitable for indoor and moderate-moisture environments. Licensed tradespeople and maintenance technicians installing or servicing equipment with hex socket fasteners will find this a straightforward replacement or new-install option.

Key Features

• 1/4-28 UNF fine-pitch thread for tighter engagement and improved vibration resistance
• Fully threaded 1-inch length under head for maximum thread engagement across material thickness
• 3/16-inch hex socket drive compatible with standard hex keys and T-handle drivers
• 18-8 stainless steel construction for corrosion resistance in moderate-exposure environments
• Bright uncoated finish - no coating buildup to interfere with thread fit or torque values
• Meets ASME B18.3, ASTM A574, and ASTM F837 dimensional and material standards

Compatibility

Designed as a standard 1/4-28 UNF hex socket cap screw per ASME B18.3. Fits any application specifying a 1/4-28 UNF fully threaded socket cap screw with a 3/16-inch hex drive in stainless steel 18-8.

Installation Notes

Install with a 3/16-inch hex key, T-handle driver, or hex bit on a torque wrench. De-energize and depressurize any equipment before accessing fastened assemblies. Apply anti-seize compound when threading stainless fasteners into stainless tapped holes to prevent galling. Follow applicable mechanical or equipment specifications for torque requirements - do not over-torque fine-thread stainless hardware.