Value Collection 49NU149 7/8-9 Unc Heavy Hex Lock Nut Nylon Insert

Product Description

The VALUE COLLECTION 49NU149 is a 7/8-9 UNC Grade 2 heavy hex lock nut with a nylon insert, designed to maintain thread engagement under vibration and dynamic loading. The nylon insert collar deforms around mating threads to create prevailing torque resistance, reducing the risk of loosening without the need for adhesives or secondary locking hardware. Constructed from uncoated steel, this heavy hex nut features a 1-7/16 inch width across flats and a 31/32 inch height. It is suited for structural, mechanical, and equipment fastening applications where a larger bearing surface and positive thread locking are required.

This heavy hex lock nut is used in general industrial, construction, and mechanical assembly applications where standard hex nuts do not provide sufficient bearing surface or vibration resistance. The 7/8-9 UNC thread size is common in structural steel connections, heavy equipment frames, and utility hardware installations. Uncoated steel construction makes it appropriate for interior or protected environments. Installation is performed by maintenance technicians, millwrights, ironworkers, and general mechanical trades.

Key Features

• Nylon insert provides prevailing torque locking without additional hardware
• Heavy hex profile offers a larger 1-7/16 inch width across flats for increased wrench engagement
• 7/8-9 UNC thread specification for compatibility with standard unified coarse thread fasteners
• Grade 2 steel construction meets standard commercial fastener load requirements
• 31/32 inch height provides greater thread engagement depth than standard hex lock nuts
• Uncoated finish suitable for dry or controlled indoor environments

Compatibility

Designed for use with 7/8-9 UNC externally threaded fasteners in heavy hex fastener applications requiring a nylon insert prevailing-torque lock nut.

Installation Notes

Installation should be performed with a wrench sized for the 1-7/16 inch heavy hex profile. Nylon insert lock nuts are intended for single-use applications and should not be reused once removed, as the insert loses clamping effectiveness after initial installation. Ensure mating bolt threads are clean and free of damage before installation. Follow applicable torque specifications from the governing project or equipment documentation.