The M4-22 PRO Compliant is a premium .22 caliber semi-automatic tactical rimfire rifle with aluminum upper and lower receivers and all the features of a true M4. The M4-22 PRO is largely mil-spec compatible and will accept most AR15 stocks, handguards and sights. The M4-22 has the look, feel and controls of a true M4 and is a perfect platform for competition and training applications or backyard plinking.