The HK45T includes several user-inspired enhancements including changeable grip panels (backstraps), a Picatinny MIL-STD-1913 accessory rail, better ergonomics, and more ambidextrous controls. The HK45 uses an HK proprietary O-ring barrel for precise barrel-to-slide lockup and optimal accuracy. HK45 barrels are made using the famous HK cold-hammer forging process for superior performance. Using HK's unique internal mechanical recoil reduction system reduces the recoil forces imparted to the weapon and shooter by as much as 30%, improving shooter control during rapid firing and increasing component service life. Capable of firing standard .45 ACP ball through +P ammunition, the HK45 combines the accuracy, modularity, reliability and minimum 20,000 round service life of the famed USP45 series with the improved ergonomics of the P2000 series pistols. HK45T models have threaded barrels for use with muzzle-mounted sound suppressors.
Variant 1 is a double action/single action with SAFE position control lever (manual safety/decocking lever) on left side of frame.