S-99291A470 7/16"-20 Locknuts

Key Features & Benefits at a Glance

• Superior vibration resistance through top lock distorted thread design, preventing loosening in high-stress environments
• Enhanced corrosion protection with black-oxide steel finish, extending service life in industrial applications
• Precise thread engagement with Class 2B UNF fine threads, ensuring reliable fastening and reduced cross-threading risk
• Heavy-duty performance meeting ASTM Grade C standards, providing consistent strength for demanding mechanical assemblies
• Easy installation and removal with standard 11/16" external hex profile, compatible with common wrench tools
• Regulatory compliance assurance with RoHS 3 and REACH SVHC standards, meeting international environmental requirements
• Optimized for fine-thread applications with 7/16"-20 UNF right-hand threads, delivering superior clamping force in precision assemblies

Professional Applications & Engineering Value

This black-oxide steel locknut addresses critical vibration-induced failure points in industrial machinery, automotive systems, and heavy equipment. The distorted thread technology creates controlled interference along the top threads, generating permanent locking action without requiring additional locking components. The UNF fine thread configuration provides superior tension distribution and better fatigue resistance compared to coarse threads, while the external hex drive style ensures reliable torque application in confined spaces. Engineered for high-stress applications where vibration and dynamic loads threaten joint integrity, this fastener maintains clamping force through thermal cycling and mechanical shock, reducing maintenance frequency and preventing costly downtime in production environments.

Specification Summary & Compliance

This 7/16"-20 UNF locknut features Class 2B thread fit for precision engagement with mating components, manufactured to ASTM Grade C mechanical properties for consistent performance. The distorted thread locking mechanism conforms to industrial locking standards, while dimensional specifications include 11/16" width across flats and 3/8" height. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations ensures environmental responsibility and workplace safety standards are met for global industrial applications.