S-91144A125 21 mm ID x 37 mm OD DIN 6916, ISO 7416 Structural Washers

Key Features & Benefits at a Glance

• Enhanced Load Distribution - 37mm outer diameter provides superior surface coverage to prevent joint loosening and surface damage under high stress
• Exceptional Durability - Black steel construction with Rockwell C45 hardness ensures long-term performance in demanding industrial environments
• Precision Fit for M20 Fasteners - 21mm inner diameter guarantees optimal compatibility with M20 screws, eliminating installation issues
• Robust Thickness Design - 3.7-4.3mm thickness range delivers reliable spacing and vibration resistance in heavy machinery applications
• International Standard Compliance - Manufactured to DIN 6916 and ISO 7416 specifications for consistent quality and global project acceptance
• Environmental Responsibility - RoHS 3 and REACH compliance ensures safe usage while meeting modern regulatory requirements
• Metric System Optimization - Metric measurements provide seamless integration with international engineering designs and replacement part inventories

Professional Applications & Engineering Value

This heavy-duty M20 flat washer addresses critical engineering challenges in industrial assembly where vibration resistance and load distribution are paramount. The black steel material with Rockwell C45 hardness provides exceptional resistance to deformation under extreme pressure, making it ideal for construction equipment, heavy machinery, and structural steel applications. The precise 21mm ID ensures perfect alignment with M20 fasteners while the 37mm OD creates an optimal bearing surface to prevent embedment and distribute clamping forces effectively. Engineered to DIN 6916 and ISO 7416 standards, this washer delivers reliable performance in high-vibration environments where joint integrity is critical to operational safety and equipment longevity.

Specification Summary & Compliance

This metric flat washer features precise dimensional specifications with 21mm inner diameter, 37mm outer diameter, and 3.7-4.3mm thickness range. Manufactured in compliance with DIN 6916 and ISO 7416 international standards, ensuring dimensional accuracy and performance consistency. The product meets RoHS 3 (2015/863/EU) compliance for hazardous substance restrictions and REACH (EC 1907/2006) compliance for chemical safety, including the latest SVHC requirements as of January 17, 2023. The black steel construction maintains Rockwell C45 hardness specifications for reliable mechanical performance in industrial applications.