Black Washer - 3/8 ID x 5/8 OD Chamfer (1)

The Black Washer - 3/8 ID x 5/8 OD Chamfer is a precision-engineered fastener component manufactured by ARP, a trusted leader in high-performance fastening solutions. This chamfered flat washer is designed for applications requiring superior clamping stability and load distribution. Whether you're assembling critical engine components, securing structural joints, or building custom machinery, this washer serves as an essential foundation for reliable, long-lasting connections that resist loosening and maintain consistent preload over time.

Constructed from chromoly steel and finished in black oxide, the Black Washer - 3/8 ID x 5/8 OD Chamfer delivers exceptional durability and corrosion resistance in demanding environments. The chamfered edge design—a key feature that distinguishes it from standard flat washers—reduces stress concentration and promotes smooth load transfer across bolt interfaces. With an inner diameter of 3/8 inch, outer diameter of 5/8 inch, and thickness of 0.062 inch, this washer is engineered to ARP specifications and maintains the tight tolerances necessary for critical fastening applications. The black oxide coating provides both functional protection and a professional appearance while ensuring compatibility with ARP fastener systems.

Builders and technicians rely on ARP washers in high-performance engine builds, automotive restorations, and industrial assembly where standard hardware cannot guarantee reliability. The 3/8-inch bore size pairs seamlessly with corresponding ARP bolts and studs, making this washer ideal for cylinder head assemblies, intake manifold installations, and transmission mounting points. Individual units allow for flexible kit assembly and replacement, ensuring you maintain consistent fastening standards throughout your project. For applications where vibration, thermal cycling, or extreme loads threaten joint integrity, the Black Washer - 3/8 ID x 5/8 OD Chamfer is the professional choice.