The Spike's Tactical Muzzle Device Alignment Set is made to replace the peel washer commonly shipped with muzzle brakes and suppressors. This kit allows you to properly time your muzzle device so I will be positioned properly on your rifle for optimum performance.
Large Shim is for _ rotation adjustment as well as for barrels with relief cuts. The medium shims each give you 45 degrees of rotation. The small shim provides even finer adjustments.