The Canadian M203A1 by Diemaco (now Colt Canada) is a similar design with a different mounting system that does not require mounting points of the same profile as the M16A1 rifle's.Diemaco M203A1. Retrieved on January 5, 2008. The weapon's 9-inch barrel slides further forward than the standard American models, which allows longer rounds to be loaded. This model is identifiable by the increased distance between the grenade launcher's barrel axis and the rifle's. This weapon may no longer be in production, but is still in use.
