Black Washer - 9/16 ID x 1 OD 2pk

The Black Washer – 9/16 ID x 1 OD 2pk (ARP 200-8525) is a precision fastening component engineered for demanding mechanical and automotive applications where standard hardware falls short. These flat washers distribute load across a wider surface area, preventing bolt head or nut penetration into softer materials while maintaining structural integrity under high-stress conditions. Whether you're assembling engine components, reinforcing critical joints, or working with specialized machinery, this two-pack delivers the reliability required by professional technicians and serious enthusiasts.

Manufactured from chromoly steel and finished in black oxide, these washers combine superior corrosion resistance with exceptional durability across temperature extremes and harsh environments. The 9/16-inch inner diameter (ID) accommodates standard fasteners while the 1-inch outer diameter (OD) provides optimal load distribution, and the 0.12-inch thickness ensures rigidity without excess material weight. Black oxide coating protects against rust and oxidation, making these washers ideal for both interior engine bays and outdoor applications where moisture exposure is inevitable.

These washers benefit engine builders, transmission assemblers, and anyone performing precision fastening work on high-performance machinery or restoration projects. The two-pack format ensures you have spares for replacement or future builds, reducing downtime and project interruption. Installation is straightforward: simply place the washer between the bolt head or nut and the material surface before tightening, allowing the larger OD to distribute clamping force evenly. Compatible with any fastener system using 9/16-inch bolts, these chromoly washers are essential inventory for shops and home garages serious about quality assembly standards.