Originally designed for the American market, the USP has found international acceptance as an accurate and ultra-reliable handgun. Features favored by U.S. law-enforcement and military users provided much of the design criteria for the USP. All USPs use a fiber-reinforced polymer frame stiffened by stainless steel inserts at areas subject to stress and friction. 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. The modular design of the USP's internal components allows the control lever function to be switched from the left to the right side of the pistol for left-handed shooters. Universal mounting grooves under the barrel allow for accessory installation. The trigger guard is oversized for use with gloves. The USP Variant 1 is capable of firing either single or double-action.