S-90673A103 3/8"-16 Locknuts

Key Features & Benefits at a Glance

• Superior vibration resistance through distorted thread top lock technology that maintains secure fastening under extreme conditions
• Exceptional durability and corrosion protection with black-oxide steel construction meeting Grade 5 strength requirements
• Reliable clamping force provided by coarse 3/8"-16 UNC threads designed for heavy-duty industrial applications
• Easy installation and removal with standard external hex drive compatible with common wrench tools
• Precision thread fit with Class 2B tolerance ensuring consistent performance and proper mating with corresponding bolts
• Environmental compliance assurance meeting both REACH and RoHS 3 standards for safe industrial use
• Right-hand threading compatibility with standard assembly procedures for streamlined operations

Professional Applications & Engineering Value

This Grade 5 black-oxide steel locknut delivers critical vibration resistance in demanding industrial environments where loosening under dynamic loads poses significant safety risks. The distorted thread top lock design creates consistent interference that prevents back-off without requiring additional locking components, simplifying assembly while maintaining exceptional clamping force. Engineered with coarse UNC threads, this external hex locknut excels in heavy machinery, automotive systems, and construction equipment where vibration-resistant fastening is paramount. The black-oxide surface treatment provides corrosion resistance while the standardized 9/16" hex profile ensures compatibility with common torque tools, making it ideal for maintenance and production lines requiring reliable, repeatable performance.

Specification Summary & Compliance

This locknut features 3/8"-16 UNC coarse threads with Class 2B thread fit for precision engagement, manufactured to Grade 5 strength standards. The external hex drive measures 9/16" across flats with a height of 3/8". The product is fully compliant with REACH (EC 1907/2006) and RoHS 3 (2015/863/EU) environmental regulations, ensuring safe use across various industrial applications while maintaining consistent dimensional accuracy and performance reliability.