Value Collection KEPI0-40-100BX K-lock Hex Nut 4-40

Product Description

The VALUE COLLECTION KEPI0-40-100BX is a 4-40 UNC K-Lock hex nut with an integrated external tooth lock washer, manufactured from steel with a zinc plating finish. This one-piece fastener combines a standard hex nut with a serrated external tooth washer that bites into the mating surface under torque, resisting loosening caused by vibration or dynamic loads. The zinc plating provides a baseline level of corrosion resistance for general indoor and light-duty applications. It is sized for 4-40 Unified National Coarse thread fastening, making it suited to small-diameter threaded assemblies in light mechanical, electrical panel, and control enclosure work.

This K-Lock nut is used in residential and light commercial applications wherever a 4-40 threaded screw requires a secure, vibration-resistant connection. Typical install scenarios include control board mounting, electrical enclosure assembly, HVAC equipment access panels, and small-component brackets. The external tooth design makes it well suited for sheet metal and stamped steel assemblies where the washer teeth can engage the base material surface directly. The washer diameter measures 9/32 inches and the width across flats measures 1/4 inch.

Key Features

• 4-40 UNC thread size for small-diameter fastening applications
• External tooth lock washer integrated into the nut for single-piece installation
• Zinc-plated steel construction provides corrosion resistance for general use
• Serrated teeth resist loosening under vibration and dynamic load conditions
• 9/32-inch washer diameter with 1/4-inch width across flats
• Sold in multiples of 100 per minimum order quantity

Compatibility

Designed for use with 4-40 UNC threaded screws and bolts in standard inch-series threaded assemblies across light mechanical, electrical, and HVAC control applications.

Installation Notes

Installation is performed by hand and standard hex tooling sized for a 1/4-inch across-flats profile. De-energize any electrical panel or control circuit before installing or removing fasteners in live enclosures, in accordance with NEC lockout/tagout requirements. Avoid over-torquing, as the small thread size and light tooth profile can be damaged by excessive force. Ensure mating surfaces are clean and free of coatings that would prevent the external teeth from engaging properly.