Holo-krome 780110019 Hex Socket Cap Screw 4-40 Unc

Product Description

The HOLO-KROME 780110019 is a hex socket cap screw designed for precision fastening applications in mechanical assemblies, instrumentation, and light-duty structural connections. The screw features a 4-40 UNC thread size and a 3/16-inch length under head, with full threading along its entire shank. Drive engagement is made through a 3/32-inch internal hex socket, requiring an appropriately sized hex key or Allen driver. Constructed from 18-8 stainless steel with a bright, uncoated finish, this fastener resists corrosion in moderate-moisture environments. It conforms to ASME B18.3 and ASTM F837 standards, making it suitable for applications where dimensional and material traceability are required.

This fastener is used in applications where a low-profile, high-strength cap screw is needed in a compact form factor. The 4-40 thread is common in precision instruments, electrical enclosures, small mechanical assemblies, and light equipment panels. Trade professionals in electrical, HVAC controls, and mechanical service work encounter this size when servicing control panels, mounting small components, or replacing fasteners in tight clearance areas. The minimum order quantity is 100 pieces, making this suitable for shop stock or production use where consistent supply of this thread size is required.

Key Features

• 4-40 UNC thread size with full threading along the entire shank length
• 3/16-inch length under head for flush or recessed fastening in thin material
• 3/32-inch hex socket drive for precise torque application in tight spaces
• 18-8 stainless steel construction provides corrosion resistance in moderate-moisture environments
• Bright, uncoated finish maintains dimensional accuracy and avoids coating buildup on threads
• Conforms to ASME B18.3 and ASTM F837 for dimensional and material compliance

Compatibility

Designed as a standard OEM-style replacement or stock fastener for assemblies requiring 4-40 UNC hex socket cap screws per ASME B18.3 specifications.

Installation Notes

Install using a calibrated 3/32-inch hex key or Allen driver to avoid rounding the socket drive. De-energize and lock out any electrical or mechanical assembly before replacing fasteners on live equipment. Stainless steel fasteners are susceptible to galling on installation — apply an appropriate anti-seize compound when fastening into stainless or aluminum threads under repeated service cycles. Follow applicable mechanical codes and equipment manufacturer guidelines for fastener torque and thread engagement requirements.