The HK MP5 A5 Semi-Automatic Rifle is the classic configuration of the MP5 submachine gun developed in the mid-1960’s. It includes a standard forearm, retractable stock and compensator. The HK MP5 A5 Semi-Automatic Rifle in .22 L.R. is manufactured exclusively by Walther under license from HK. It is the only genuine HK tactical rimfire replica available in the world.