S-99638A500 7/16"-20 MS21045-7 Locknuts

Key Features & Benefits at a Glance

• Superior vibration resistance through flex-top locking technology that maintains consistent clamping force under extreme conditions
• Enhanced corrosion protection with cadmium yellow-chromate plating that withstands harsh industrial and aerospace environments
• Precise thread engagement with Class 3B fit ensuring reliable, permanent fastening without cross-threading issues
• Industry-standard compliance meeting MS21045-7 specifications for critical aerospace and defense applications
• Easy installation and removal with standard external hex drive design compatible with common wrench tools
• Optimized for fine-thread applications with 7/16"-20 UNF right-hand threads providing superior holding power
• Durable steel construction delivering long-term reliability and consistent performance in high-stress environments

Professional Applications & Engineering Value

This MS21045-7 certified locknut delivers critical engineering solutions where vibration-induced loosening poses significant safety risks. The flex-top locking mechanism creates permanent deformation that resists rotational forces, making it ideal for aerospace assemblies, heavy machinery, and industrial equipment subjected to constant motion. The cadmium yellow-chromate plated steel construction provides dual protection against corrosion while maintaining electrical conductivity requirements. With Class 3B thread fit and UNF fine threads, this locknut ensures precise alignment and maximum thread contact area, preventing catastrophic failures in critical applications where reliability is non-negotiable.

Specification Summary & Compliance

This high-performance locknut features 7/16"-20 UNF fine threads with Class 3B internal thread fit for exceptional precision. The external hex drive measures 11/16" across flats with a total height of 15/32". Manufactured to meet MS21045-7 military specifications and compliant with relevant aerospace standards, this right-hand thread locknut utilizes flex-top locking technology for permanent fastening solutions. The cadmium yellow-chromate plating provides superior corrosion resistance while maintaining compliance with industry requirements for critical applications.