The Colt Automatic Rifle-15 or CAR-15 is a family of M16 rifle–based firearms marketed by Colt in the 1960s and early 1970s. However, the term “CAR-15” is most commonly associated with the Colt Commando (AKA: XM177); these select-fire carbines have ultrashort 10.5-inch (270 mm) and 11.5-inch (290 mm) barrels with over-sized flash suppressors.
The CAR-15 name was an attempt to re-associate the AR-15 name with Colt, since the AR initially stood for ArmaLite, the original manufacturer of the ArmaLite AR-15. Colt later abandoned the CAR-15 concept, but continued to make carbine variations, using the “M16” brand for select-fire models and the “Colt AR-15” brand for semi-automatic models. However, in present usage, “CAR-15” is the generic name for all carbine-length variants made before the M4 carbine.