S-96345A210 4-40 MS21044C04, NASM21044 Locknuts

Key Features & Benefits at a Glance

• Superior vibration resistance through the durable nylon insert that maintains locking force in high-motion environments
• Excellent corrosion resistance provided by 18-8 stainless steel construction for extended service life in harsh conditions
• High-temperature performance with nylon insert rated up to 250°F (121°C) for reliable operation in demanding thermal environments
• Precision installation ensured by Class 3B thread fit for consistent torque values and secure fastening
• Industry-standard compatibility meeting MS21044C04 and NASM21044 specifications for guaranteed quality and interchangeability
• Easy installation and removal with standard external hex drive design compatible with common wrench tools
• Environmental compliance with RoHS 3 and REACH regulations for safe use across global industrial applications

Professional Applications & Engineering Value

This 4-40 UNC nylon insert locknut delivers critical vibration resistance where traditional fasteners fail. The 18-8 stainless steel body provides exceptional corrosion resistance while the precision-molded nylon insert creates consistent locking force that won't loosen under sustained vibration. Engineered for industrial applications requiring reliable performance in challenging environments, this external hex locknut maintains its integrity across temperature fluctuations up to 250°F. The coarse UNC thread with Class 3B fit ensures rapid installation without compromising security, making it ideal for assembly lines, machinery, and equipment where vibration-induced loosening poses operational risks. Certified to MS21044C04 and NASM21044 standards, this locknut guarantees compatibility and performance in aerospace, automotive, and heavy equipment applications.

Specification Summary & Compliance

This precision-engineered locknut features 4-40 UNC coarse threads with Class 3B thread fit for optimal engagement and torque consistency. The external hex design measures 1/4" width and 5/32" height for standard tool compatibility. Manufactured to meet MS21044C04 and NASM21044 specifications, ensuring dimensional accuracy and performance reliability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, containing no substances of very high concern above threshold limits.