Specifications and Features: – Product Group: Air Pistols – Brand: Heckler & Koch – Velocity (FPS): 400 – Caliber: 0.177 (4.5mm) – Ammo Type: Steel BBs – FPS w/Lead Pellet: 400 – Barrel Length: 4.5 – Total Length (inches): 7.5 – Capacity: 22 – Barrel Type: Smooth – Front Sight Type: Blade – Fixed – Rear Sight Type: Notch – Fixed – Action: Semi Auto – Safety Type: Manual – Power: CO2 – Trigger Action: Double – CO2 powered BB guns are great fun for plinking and target shooting. Check out this HK USP. It holds 22 rounds in a heavyweight magazine that also houses the CO2 cylinder that powers this BB pistol. It has an ambidextrous magazine release integrated accessory rail and realistic hammer movement. This is a great practice pistol for 9mm USP owners. For just pennies a shot you can shoot for hours. – UMAREX holds the worldwide exclusive HK-trademark and exterior design copy license for use with this UMAREX product granted by HK Inc. U.S.A.