S-90412A200 21 mm ID x 33 mm OD DIN 6797 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance with external teeth that bite into mating surfaces to prevent loosening under dynamic loads
• Excellent corrosion resistance in harsh environments thanks to 316 stainless steel construction
• Precise dimensional compatibility with M20 fasteners (21mm ID, 33mm OD) ensuring perfect fit and optimal performance
• Maximum locking force achieved through precisely engineered tooth geometry and 1.2-1.6mm thickness range
• Industry-standard compliance with DIN 6797 specifications for reliable, predictable performance
• Environmental and safety compliance with RoHS 3 and REACH regulations for industrial applications
• Enhanced durability through hardened external teeth that maintain locking effectiveness through multiple installations

Professional Applications & Engineering Value

This M20 external tooth lock washer delivers critical vibration resistance in demanding industrial environments where fastener security is paramount. The 316 stainless steel construction provides exceptional corrosion resistance, making it ideal for chemical processing, marine applications, and outdoor equipment exposed to moisture and corrosive elements. The external tooth design according to DIN 6797 standards ensures maximum biting action into both the fastener and workpiece, creating a mechanical lock that prevents rotation and loosening under continuous vibration and thermal cycling. This metric lock washer solves common engineering challenges in heavy machinery, automotive assemblies, and structural applications where traditional flat washers fail to maintain bolt tension, reducing maintenance frequency and preventing equipment failure in critical industrial applications.

Specification Summary & Compliance

This precision external tooth lock washer features dimensional specifications of 21mm internal diameter, 33mm external diameter, and 1.2-1.6mm thickness range, engineered specifically for M20 fasteners. Manufactured in compliance with DIN 6797 standards for dimensional accuracy and performance requirements. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and regulatory acceptance for industrial use across global markets.