Barrel Shim Set to be used to correctly orient a timed muzzle device. This set is used with our 5.56mm Q.D. Muzzle Brakes. This shim kit has an inner diameter of 5/8 - Included with this shim kit are shims with the following thicknesses: - 2x 0.002 - 5x 0.005 - 1x 0.020
Determined at checkout.