The MWG converts the magazine well into a comfortable vertical grip for better control of the weapon. Allows a tight stance for speed and maneuverability. Prevents pressure on non-free-floating handguards that can affect accuracy. Keeps hands off the magazine. The MWG also functions as a flared and extended magazine well to speed reloads. Fits MIL-SPEC AR .223/5.56 lowers or any multi cal. Will not fit lowers with non mil-spec silhouette .slight modifications may be needed with some lowers and or magazines.