 Production began in late 1944 and they were on issue by the March 1945 Operation Varsity airborne crossing of the Rhine into Germany.The pistol was popular with the British airborne forces as well as covert operations and commando groups such as the Special Operations Executive (SOE), the U.S. Office of Strategic Services (OSS) and the British Special Air Service (SAS) Regiment.Inglis High-Powers made for Commonwealth forces have the British designation 'Mk 1', or 'Mk 1*' and the manufacturer's details on the left of the slide.