This same recoil reduction system has been tested and proven in the HK Mark 23 pistol developed for the U.S. Using a modified Browning-type action with a special patented recoil reduction system, the USP recoil reduction system reduces recoil effects on pistol components and also lowers the recoil forces felt by the shooter. The USP control lever, a combination safety and decocking lever, is frame mounted and quickly accessible, unlike the slide-mounted safeties common on many semi-automatic pistols. HK pioneered this use of polymer materials in the production of handguns more than 30 years ago with the development of the VP70Z and P9S pistols. All USPs use a fiber-reinforced polymer frame stiffened by stainless steel inserts at areas subject to stress and friction. The controls are uniquely American, influenced by such famous designs as the Government Model 1911 pistol. law enforcement and military users provided much of the design criteria for the USP. Originally designed for the American market, the USP (Universal Self-loading Pistol) has found international acceptance as an accurate and ultra-reliable handgun.
