S-90488A120 0.169" ID x 0.278" OD Heavy-Vibration-Resistant Spring Lock Washers for Socket Head Screws

Key Features & Benefits at a Glance

• Superior vibration resistance with dual top/bottom serrations that maintain constant tension and prevent fastener loosening under dynamic loads
• Exceptional corrosion resistance thanks to 18-8 stainless steel construction, ideal for harsh industrial environments and outdoor applications
• Optimized dimensional precision with 0.169" ID and 0.278" OD ensuring perfect fit for M4 screws and consistent performance
• Enhanced durability from Rockwell C42 hardness rating that provides excellent spring-back characteristics and long service life
• Reliable locking performance through spring tension mechanism that compensates for thermal expansion and material relaxation
• Regulatory compliance assurance with RoHS 3 and REACH compliance meeting strict international environmental standards
• Space-efficient design with compact 0.039" overall height and 0.020" thickness suitable for confined assembly spaces

Professional Applications & Engineering Value

This M4 spring lock washer delivers critical engineering solutions for applications where vibration-induced loosening compromises assembly integrity. The dual serration technology on both top and bottom surfaces creates multiple biting edges that dig into mating surfaces, effectively resisting rotational forces in heavy machinery, automotive systems, and electrical enclosures. Manufactured from 18-8 stainless steel, it provides inherent corrosion resistance that outperforms carbon steel alternatives in humid or chemically aggressive environments. The Rockwell C42 hardness ensures the washer maintains its spring tension through repeated compression cycles, while the precise metric dimensions (0.169" ID / 0.278" OD) guarantee proper seating on M4 fasteners. This combination of features addresses common failure points in vibration-prone assemblies, extending maintenance intervals and reducing downtime.

Specification Summary & Compliance

This metric spring lock washer features precise dimensional specifications including 0.169" internal diameter, 0.278" outer diameter, 0.020" thickness, and 0.039" overall height, engineered for M4 screw applications. The manufacturing employs 18-8 stainless steel with Rockwell C42 hardness to ensure consistent performance. The product fully complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, meeting the latest environmental standards for industrial components. The dual serration design follows industry-standard locking washer principles for reliable vibration resistance in demanding applications.