Infinite Product Solutions 13.5mm Crush Washer Black Oxide. 5mm Crush Washer a robust and reliable addition to your firearm accessories. Specifications for Infinite Product Solutions 13.5mm Crush Washer: Manufacturer: Infinite Product Solutions Fabric/Material: 304 Stainless Steel Last Chance: Yes Weight: 0.064 oz Width: 0.82 in Length: 0.82 in Height: 0.15 in Caliber: 9mm Luger Features of Infinite Product Solutions 13.5mm Crush Washer Provides over 1 full rotation (360 degrees) for proper muzzle alignment Corrosion Resistant Package Contents: Infinite Product Solutions 13.5mm Crush Washer Infinite Product Solutions CW-304-OXD-135: 13.5mm Crush Washer Black Oxide