S-91100A130 4.3 mm ID x 12 mm OD DIN 9021 Oversized Washers

Key Features & Benefits at a Glance

• Superior corrosion protection with zinc-plated steel construction, extending service life in demanding environments
• Precise M4 screw compatibility with 4.3mm inner diameter for secure, vibration-resistant fastening
• Optimized load distribution through 12mm outer diameter design, preventing surface damage and joint loosening
• Consistent performance ensured by 0.9-1.1mm thickness tolerance and Rockwell B56 hardness for reliable pressure resistance
• Guaranteed dimensional accuracy through strict DIN 9021 standard compliance for seamless integration
• Environmental responsibility with full RoHS 3 and REACH compliance, meeting global regulatory requirements
• Enhanced durability through hardened steel material, maintaining integrity under repeated stress cycles

Professional Applications & Engineering Value

Engineered for precision industrial assembly, these M4 flat washers provide critical solutions for vibration management and surface protection in machinery, automotive, and electrical enclosures. The zinc-plated steel construction delivers corrosion resistance in humid or chemically aggressive environments, while the DIN 9021 standardized dimensions ensure perfect fit with metric fastening systems. With controlled 0.9-1.1mm thickness and Rockwell B56 hardness, these washers maintain consistent clamping force and prevent galvanic corrosion between dissimilar metals, addressing common fastener failure points in B2B applications.

Specification Summary & Compliance

Manufactured to DIN 9021 dimensional standards with 4.3mm inner diameter, 12mm outer diameter, and 0.9-1.1mm thickness tolerance. Features Rockwell B56 hardness for consistent mechanical performance. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and regulatory acceptance for international industrial supply chains.