S-94191A123 5/8"-18 Fed. Spec. FF-N-836, MS51968-21 Hex Nuts

Key Features & Benefits at a Glance

• Exceptional strength and reliability with Grade 8 classification, ensuring high load-bearing capacity for demanding industrial applications
• Superior corrosion resistance thanks to black-oxide steel construction, extending service life in harsh environments
• Precise fine thread engagement with 5/8"-18 UNF Class 2B threads, providing secure, vibration-resistant fastening
• Standard external hex design for easy installation using common tools, reducing assembly time and labor costs
• Full regulatory compliance with Fed. Spec. FF-N-836, MS51968-21, RoHS 3, and REACH standards, ensuring workplace safety and environmental responsibility
• Optimized dimensional consistency with 15/16" width and 35/64" height, guaranteeing reliable performance in repetitive applications
• Right-hand thread configuration for straightforward installation in standard industrial equipment and machinery

Professional Applications & Engineering Value

These Grade 8 black-oxide steel hex nuts deliver critical performance advantages in heavy-duty applications where fastener failure is not an option. The combination of UNF fine threading and Class 2B thread fit ensures superior resistance to vibration loosening, making them ideal for machinery, automotive assemblies, and structural frameworks subject to dynamic loads. The black-oxide surface treatment provides essential corrosion protection without compromising dimensional accuracy, while the standard hex profile enables quick installation and removal with common wrenching tools. Engineered to meet rigorous military and industrial specifications, these nuts solve common challenges of thread stripping, galling, and environmental degradation in demanding operational conditions.

Specification Summary & Compliance

This 5/8"-18 UNF hex nut features Class 2B thread fit per unified thread standards, ensuring precise dimensional tolerance for reliable engagement. Manufacturing complies with Fed. Spec. FF-N-836 and MS51968-21 requirements, guaranteeing consistent quality and performance. The product is fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant (including 224 SVHC substances as of 06/10/2022), meeting current environmental and safety regulations for industrial components.