Holo-krome 720000210 Hex Socket Cap Screw 4-40 Unc

Product Description

The HOLO-KROME 720000210 is a hex socket cap screw designed for precision fastening in mechanical assemblies, tooling fixtures, and equipment manufacturing. It features a 4-40 UNC thread and a 7/16-inch length under head with full threading throughout. The drive is a 3/32-inch internal hex socket, requiring an Allen wrench or hex key for installation. Constructed from alloy steel with a black oxide finish, it delivers solid tensile strength in a compact, low-profile fastener. This screw is suited for applications where tight tolerances and reliable clamping are required. It conforms to ASME B18.3 and ASTM A574 standards.

This fastener is commonly used in light mechanical assemblies, instrumentation, small-bore machine components, and precision tooling where a #4-40 thread is specified. The black oxide coating provides mild corrosion resistance in dry or lightly humid indoor environments. It is appropriate for use in both production assembly and maintenance repair operations where compact, high-strength fasteners are required. This screw is typically installed by machinists, mechanical assemblers, and maintenance technicians working with small-format hardware.

Key Features

• 4-40 UNC thread for compatibility with standard #4-40 tapped holes
• Fully threaded shank along the 7/16-inch length under head
• 3/32-inch hex socket drive for use with standard Allen wrenches
• Alloy steel construction meets ASTM A574 mechanical requirements
• Black oxide finish provides mild corrosion resistance and reduces light reflection
• Conforms to ASME B18.3 dimensional standards

Compatibility

Designed as a standard replacement or production fastener for any application specifying a 4-40 UNC fully threaded hex socket cap screw with a 7/16-inch length under head per ASME B18.3.

Installation Notes

Install using a properly sized 3/32-inch hex key or Allen driver to avoid rounding the socket. Ensure the mating tapped hole is clean and free of debris before threading. Do not exceed the torque rating for a #4-40 alloy steel screw, and follow applicable ASME or equipment manufacturer fastener torque guidelines. Replace any fastener showing thread damage or socket wear.