Value Collection 31-NU-25C Hex Lock Nut 1/4-20 18-8 Ss

Product Description

The VALUE COLLECTION 31-NU-25C is a 1/4-20 UNC heavy hex lock nut with a nylon insert locking mechanism, manufactured from 18-8 stainless steel with a bright, uncoated finish. The nylon insert compresses against mating threads under torque, creating mechanical resistance to loosening from vibration and thermal cycling. At 3/8 inches tall with a 1/2-inch width across flats, this fastener is sized for standard 1/4-20 threaded assemblies. It is installed by licensed tradespeople and maintenance professionals across HVAC, plumbing, and general mechanical applications where stainless corrosion resistance is required.

This lock nut is suited for indoor and outdoor installations where fastener corrosion is a concern, including equipment mounting, panel assembly, and mechanical connections exposed to moisture or mild chemicals. The 18-8 stainless steel grade provides solid resistance to rust and oxidation without a surface coating. The right-hand thread direction follows standard UNC fastener convention. Applications span residential and light commercial mechanical systems, structural brackets, and equipment frame assemblies requiring reliable thread retention.

Key Features

• Nylon insert locking style resists loosening from vibration and thermal cycling
• 18-8 stainless steel construction for corrosion resistance without a coating
• 1/4-20 UNC thread size with right-hand thread direction
• Heavy hex profile: 3/8 inches height, 1/2 inches width across flats
• Bright, uncoated finish — no additional surface treatment to degrade or peel
• Width across points of 0.556 inches for precise socket or wrench fit

Compatibility

Designed as a standard UNC replacement or service fastener for any 1/4-20 threaded application requiring a nylon insert hex lock nut in 18-8 stainless steel.

Installation Notes

Install using a standard hex wrench or socket sized to 1/2 inches across flats. Power down or de-energize any associated equipment before accessing fastener assemblies in electrical or mechanical enclosures. Nylon insert lock nuts are single-use by design — the nylon deforms on first installation and may not retain full locking force if removed and reused. Follow applicable mechanical and structural codes for the specific trade application.