the earlier  5.56mm   SG 540  and is also known as the  Fass 90  ( Fusil d'assaut  90 /  Fucile d'assalto  90) in  French  /  Italian  or  Stgw 90  in  German  ( Sturmgewehr  90). CAR-15 The  Colt Automatic Rifle-15 Military Weapons System  or  CAR-15  was a family of  AR-15  and  M16