Just swap this drop in conversion with your bolt carrier group and you will be ready to shoot .22LR. Ships with a 10rd Magazine.
There may be some powder residue on the bolt as these are test fired at the factory.
Note: For Direct Gas Impingement AR-15's. Not compatible with Gas Piston Systems without removing the piston. Only for use in 5.56 NATO chambered AR-15 rifles.
Big Book Catalog, Issue:73, Page:016