S-90313A411 0.578" ID x 1.25" OD Oversized Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance thanks to 18-8 stainless steel construction, ideal for humid, chemical, or outdoor environments.
• Precise dimensional fit with a 0.578" inner diameter designed specifically for 9/16" screws, ensuring secure fastening and load distribution.
• Enhanced surface coverage from the 1.25" outer diameter, providing greater bearing surface and preventing material embedment.
• Consistent performance with a controlled thickness range of 0.050-0.080", maintaining uniformity in assembly pressure.
• Long-term reliability in demanding applications due to the material's inherent strength and durability.
• Global regulatory compliance with RoHS 3 and REACH, ensuring safe use in regulated industrial and commercial settings.
• Broad compatibility with inch-system components, simplifying sourcing and inventory for North American and international projects.

Professional Applications & Engineering Value

This 18-8 stainless steel flat washer is engineered to address common failure points in industrial assemblies, such as corrosion-induced degradation and joint loosening under vibration. Its 0.578" ID and 1.25" OD deliver optimal load distribution for 9/16" screw size fasteners, reducing stress concentrations on soft materials or painted surfaces. The corrosion-resistant properties make it suitable for marine, food processing, and chemical plant applications, where exposure to moisture or aggressive agents is frequent. By utilizing a precision washer with consistent thickness control, engineers can achieve reliable clamp load and maintain assembly integrity in heavy-duty equipment, structural frameworks, and machinery subjected to dynamic loads.

Specification Summary & Compliance

This flat washer conforms to standard inch-system dimensions with an inner diameter of 0.578", outer diameter of 1.25", and thickness ranging from 0.050" to 0.080". It is manufactured from 18-8 stainless steel for general-purpose use and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming adherence to environmental and safety standards for hazardous substance restrictions.