Holo-krome 64004 Button Socket Cap Screw 4-40 3/8in

Product Description

The HOLO-KROME 64004 is a button socket cap screw designed for threaded fastening applications that require a low-profile head and high-strength alloy steel construction. The button head profile reduces clearance requirements compared to standard socket cap screws, making it well suited for applications with limited vertical space. Driven by a 1/16-inch hex socket, the fastener delivers secure torque transfer without a protruding drive interface. Black oxide finish provides mild corrosion resistance and a consistent matte appearance. The screw is fully threaded to the head, following UNRC thread standards at a 4-40 thread size with a 3A thread fit class.

This fastener is used across a wide range of light mechanical assembly applications including enclosures, brackets, instrumentation panels, and equipment frames. Its 3/8-inch length under head and fully threaded body make it appropriate for thin-material or shallow-boss installations. The right-hand thread direction follows standard assembly convention. Installations typically call for precision-torqued fastening in clean, controlled environments. This part is sold individually but requires a minimum order quantity of 100 units per order.

Key Features

• Button head profile for low-profile installations with limited vertical clearance
• Alloy steel construction with 38 HRC hardness for high-strength fastening
• Black oxide finish for mild corrosion resistance and consistent appearance
• 1/16-inch hex socket drive for secure, tool-driven torque transfer
• Fully threaded body suits thin-material and shallow-boss applications
• Meets ANSI/ASME B18.3 and ASTM F835 fastener standards

Compatibility

Designed as an OEM-style replacement or direct-fit fastener for applications requiring a 4-40 UNC button socket cap screw conforming to ANSI/ASME B18.3 and ASTM F835 standards.

Installation Notes

Installation should be performed using a calibrated 1/16-inch hex key or hex socket driver. Ensure mating threads are clean and free of debris before assembly. Follow applicable mechanical assembly standards for torque guidance on 4-40 alloy steel fasteners. Avoid over-driving, which can strip the button head socket recess or damage mating threads.