S-91116A130 4.3 mm ID x 12 mm OD DIN 9021 Oversized Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction, ideal for humid or chemically aggressive environments
• Precise dimensional fit with 4.3mm ID ensuring secure seating on M4 screws without play or misalignment
• Enhanced load distribution from 12mm OD design, minimizing surface pressure and preventing material damage
• Consistent performance guaranteed by Rockwell B52 hardness, maintaining shape under repeated tightening cycles
• Regulatory compliance assurance with RoHS 3 and REACH standards, eliminating supply chain restrictions
• Interchangeable reliability through DIN 9021 certification, ensuring compatibility with European metric assemblies
• Optimized thickness tolerance (0.9-1.1mm) providing uniform clamping force in high-vibration applications

Professional Applications & Engineering Value

Engineered to address common industrial challenges, these M4 flat washers deliver critical solutions for precision assemblies. The 18-8 stainless steel material inherently resists rust and chemical degradation, making these metric washers indispensable in food processing, marine hardware, and outdoor equipment where moisture exposure is constant. Their DIN 9021 standardized dimensions prevent galvanic corrosion when paired with compatible M4 stainless fasteners, while the controlled Rockwell B52 hardness ensures the washers maintain flatness under dynamic loads. By distributing bearing stress across the 12mm OD, they protect soft substrates and composite materials from crushing – a key advantage in electronic enclosures and automotive subassemblies where surface integrity is paramount.

Specification Summary & Compliance

Manufactured to DIN 9021 dimensional standards with precise inner diameter (4.3mm), outer diameter (12mm), and thickness range (0.9-1.1mm). Material certification includes 18-8 stainless steel with Rockwell B52 hardness verification. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, including the latest SVHC updates, ensures unrestricted use across EU markets and environmentally sensitive applications.