S-90377A183 0.531" ID x 3" OD Oversized Washers

Key Features & Benefits at a Glance

• Exceptional corrosion resistance from black-oxide coated 18-8 stainless steel, ideal for harsh industrial environments
• Optimal load distribution with a large 3" outer diameter, reducing surface pressure and preventing material damage
• Precise fit for 1/2" screws thanks to the 0.531" inner diameter, ensuring secure fastening and alignment
• Durable construction with consistent 0.050-0.080" thickness for reliable performance under heavy loads
• Compliance with strict environmental standards, including RoHS 3 and REACH, for safe and sustainable use
• Versatile inch system compatibility, making it easy to integrate into existing industrial setups
• Long-lasting surface protection that maintains integrity in moist or chemically exposed conditions

Professional Applications & Engineering Value

Engineered for demanding industrial applications, this black-oxide 18-8 stainless steel flat washer addresses common challenges like corrosion-induced failure and uneven load bearing. The black-oxide coating enhances the natural rust resistance of 18-8 stainless steel, making it suitable for outdoor machinery, marine equipment, and chemical processing plants where moisture and corrosive agents are prevalent. Its 3" OD and precise 0.531" ID ensure a snug fit on 1/2" screws, distributing force evenly to prevent bolt loosening or surface indentation. This design is critical in structural assemblies, automotive frameworks, and heavy-duty fastening systems, providing reliable performance that reduces maintenance frequency and extends equipment lifespan.

Specification Summary & Compliance

This flat washer adheres to inch system measurements with an inner diameter of 0.531", outer diameter of 3", and thickness ranging from 0.050" to 0.080", designed specifically for 1/2" screw sizes. It conforms to standard industrial dimensional tolerances and is manufactured from 18-8 stainless steel with a black-oxide finish for enhanced durability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets rigorous environmental and safety standards for hazardous substance restrictions.