S-90377A153 0.406" ID x 0.75" OD Oversized Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance thanks to Black-Oxide coated 18-8 Stainless Steel, ideal for harsh or outdoor environments.
• Exceptional durability and load distribution with a Rockwell B68 hardness rating, reducing wear and extending service life.
• Precise fit for 3/8" screws with a 0.406" inner diameter, ensuring secure fastening and preventing loosening.
• Optimized surface coverage and stability from the 0.75" outer diameter, protecting surfaces from damage under high stress.
• Consistent performance and reliability with a controlled thickness range of 0.110" to 0.140", maintaining uniform pressure.
• Compliance with stringent environmental regulations, being RoHS 3 and REACH compliant for safe, global industrial use.
• Versatile for heavy-duty applications in the inch measurement system, suitable for various industrial and mechanical assemblies.

Professional Applications & Engineering Value

This Black-Oxide 18-8 Stainless Steel flat washer is engineered to address common industrial challenges like corrosion, vibration-induced loosening, and surface damage in demanding environments. The Black-Oxide coating enhances the inherent corrosion resistance of 18-8 stainless steel, making it perfect for outdoor equipment, marine applications, and chemical processing industries where moisture and corrosive agents are prevalent. With a precise 0.406" ID for 3/8" screws and a robust 0.75" OD, it ensures even load distribution, reduces stress on fastened materials, and minimizes maintenance needs. Its Rockwell B68 hardness provides reliable performance under heavy loads, offering long-term value in construction, automotive, and machinery assemblies by preventing fastener failure and extending component life.

Specification Summary & Compliance

This flat washer features an inner diameter of 0.406", outer diameter of 0.75", and thickness ranging from 0.110" to 0.140", designed for use with 3/8" screws in inch-based systems. Manufactured from 18-8 Stainless Steel with a Black-Oxide finish, it achieves a hardness of Rockwell B68 for consistent mechanical properties. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets environmental and safety standards for industrial applications.