S-99904A137 5/16"-24 Flange Nuts

Key Features & Benefits at a Glance

• Superior vibration resistance through serrated locking technology that bites into mating surfaces to prevent loosening under dynamic loads
• Enhanced corrosion protection with zinc-plated steel construction, extending service life in demanding industrial environments
• High-strength performance meeting Grade 5 specifications, ensuring reliable fastening in heavy-duty applications
• Precision thread engagement with UNF fine threads and Class 2B fit for secure, consistent clamping force
• Integrated flange design providing wider bearing surface (11/16" diameter) to distribute load and prevent surface damage
• Easy installation and removal using standard external hex drive with familiar 1/2" width for efficient maintenance
• Regulatory compliance meeting RoHS 3 and REACH standards for environmentally responsible manufacturing

Professional Applications & Engineering Value

This Grade 5 flange lock nut delivers exceptional engineering value through its zinc-plated steel construction and serrated locking mechanism, specifically designed to combat vibration-induced loosening in industrial machinery, automotive assemblies, and heavy equipment. The UNF fine threads (5/16"-24) provide superior thread engagement and clamping force distribution, while the integrated 11/16" flange eliminates the need for separate washers, reducing assembly time and potential failure points. The external hex drive with standard profile ensures compatibility with common tools, making it ideal for maintenance-intensive applications where reliability and quick service access are critical. This combination of vibration-resistant locking and corrosion protection addresses common fastener failure modes in demanding environments.

Specification Summary & Compliance

This flange lock nut features precision 5/16"-24 UNF fine threads with Class 2B thread fit for consistent engagement, manufactured to Grade 5 strength standards. The zinc-plated steel construction provides both corrosion resistance and durability, with dimensions including 11/16" flange diameter, 1/2" width across flats, and 9/32" height. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental responsibility and suitability for industrial applications requiring certified components.