The AR platform has become widely popular for makers of and sporting rifles. Although the designations "AR-10" and "AR-15" are respectively trademarks of ArmaLite and Colt, variants of both are made by many manufacturers. The AR-15 rifle usually comes chambered for either the military cartridge 5.56×45mm or the .223 Remington. Because of the pressures associated with the 5.56x45mm, it is not advisable to fire 5.56x45mm rounds in an AR-15 marked as .223 Rem, since this can result in damage to the rifle or injury to the shooter. The AR-15 can be converted to other calibers; it is then often referred to as an AR-15 style rifle.