S-90631A005 4-40 Locknuts

Key Features & Benefits at a Glance

• Superior vibration resistance through nylon insert locking that maintains secure fastening in dynamic environments
• Enhanced durability and corrosion protection with zinc-plated steel construction for extended service life
• Reliable high-temperature performance with nylon insert rated up to 220°F for demanding industrial applications
• Easy installation and removal with standard external hex drive design compatible with common tools
• Precise thread engagement with UNC coarse threading and Class 2B fit ensuring consistent performance
• Optimal size compatibility with 1/4" width and 9/64" height dimensions for standard assembly requirements
• Compliance with environmental regulations meeting RoHS 3 and REACH standards for global manufacturing

Professional Applications & Engineering Value

This 4-40 nylon insert locknut delivers exceptional engineering value in applications where vibration-induced loosening compromises assembly integrity. The zinc-plated steel construction provides essential corrosion resistance while maintaining mechanical strength, making it ideal for automotive, machinery, and electrical enclosures exposed to environmental stressors. The UNC coarse thread design ensures rapid installation and reliable performance in high-vibration environments, while the nylon insert creates consistent locking force without damaging mating threads. Engineered for industrial applications requiring repeated disassembly and reassembly, this locknut maintains its locking capability through multiple cycles, reducing maintenance costs and improving equipment reliability. The external hex drive facilitates quick installation with standard wrenches, streamlining assembly processes in manufacturing and maintenance operations.

Specification Summary & Compliance

This locknut features Class 2B thread fit per UNC standards, ensuring proper engagement with mating components. The zinc-plated steel construction meets industrial durability requirements while the nylon insert provides reliable locking performance. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, this fastener is suitable for global manufacturing applications requiring environmental compliance. The combination of precise dimensional control (1/4" width, 9/64" height) and standardized UNC coarse threading ensures consistent performance across industrial assemblies.