Black Washers - 12mm ID x 3/4 OD (10)

The Black Washers – 12mm ID x 3/4 OD (10) from ARP are precision fastener components designed for tactical builds, firearms assembly, and equipment maintenance where reliability is non-negotiable. Whether you're a gunsmith, armorer, or end-user performing field repairs or custom builds, these washers provide critical load distribution and fastener security in high-stress applications. In law enforcement and military contexts, even small components like washers play a vital role in maintaining weapon integrity and reducing point-load stress on receivers, rails, and mounting surfaces.

Each washer features a 12mm inner diameter that accommodates standard hardware, paired with a 3/4-inch outer diameter for optimal surface area and load spreading. The black finish provides corrosion resistance and matches tactical hardware aesthetics while protecting against moisture and environmental degradation. ARP's manufacturing standards ensure consistent thickness and flatness across the ten-piece set, critical tolerances that prevent fastener loosening under recoil, vibration, or thermal cycling—conditions that demand precision in duty rifles and field equipment.

Operators building or maintaining AR-platform rifles, precision bolt guns, or tactical equipment will benefit from stocking these washers for scope base installation, rail mounting, or receiver work where factory fasteners require supplemental components. The compact ten-pack fits easily in a field kit or maintenance pouch, making it ideal for armorer benches, mobile repair kits, and deployment packs. Installation is straightforward—position the washer under the bolt head or fastener to increase bearing surface and reduce stress concentration on aluminum or steel components prone to galling or deformation.