The HK45 was developed as a product improvement of the highly regarded USP45 first released in the 1995. The Caliber .45 ACP HK45 includes several user-inspired enhancements including changeable grip panels (backstraps) a Picatinny MIL-STD-1913 accessory rail better ergonomics and more ambidextrous controls. FEATURES: Interchangeable Grip Panels; Dual Slide Release; Enlarged Magazine Release; Picatinny Rail; Polygonal Rifling FINISH: BLACK