Holo-krome 78004 Hex Socket Cap Screw 2-56 Unc Stainless

Product Description

The HOLO-KROME 78004 is a hex socket cap screw designed for precision fastening in mechanical assemblies, instrumentation, and light-duty structural applications. Threaded 2-56 UNC and fully threaded along its 1/4 inch length under the head, this fastener accepts a 5/64 inch hex drive. It is manufactured from 18-8 stainless steel with a bright, uncoated finish, providing corrosion resistance in environments where plated carbon steel is not suitable. The fine thread form holds well under vibration and delivers consistent clamping force in close-tolerance holes. This screw is commonly installed by machinists, maintenance technicians, and mechanical assemblers working on precision equipment.

This screw is well suited for small-frame assemblies, instrument panels, enclosures, and light mechanical fixtures requiring a compact, low-profile fastening solution. The 2-56 UNC thread size is a standard choice in precision electrical and mechanical equipment where small fasteners are required. The stainless steel construction makes it appropriate for applications exposed to moisture or mild corrosive conditions where a standard steel fastener would degrade over time.

Key Features

• 2-56 UNC thread form for precision small-diameter fastening
• Fully threaded along the entire 1/4 inch under-head length
• 5/64 inch internal hex drive accepts standard hex keys
• 18-8 stainless steel construction for corrosion resistance
• Bright uncoated finish — no coating thickness to account for in close-tolerance holes
• Meets ASME B18.3 and ASTM F837 fastener standards

Compatibility

Designed as a standard-dimension replacement or stock fastener for assemblies requiring a 2-56 UNC hex socket cap screw with a 1/4 inch under-head length, conforming to ASME B18.3.

Installation Notes

Install using a calibrated 5/64 inch hex key or hex bit driver; avoid oversized or worn drivers that can strip the socket. Ensure the mating tapped hole is clean and free of debris before installation. Do not apply excessive torque — small-diameter stainless fasteners are susceptible to galling and thread seizure; use an appropriate anti-galling lubricant where torque consistency is critical. Follow applicable mechanical assembly standards for the specific equipment or enclosure being serviced.