Umarex Heckler & Koch MP5 2252330 BB 40 Rounds 400fps Air Rifle, 0.177 Caliber, Black Powered by a single 12 gram CO2 Drop free magazine Action semi auto repeater Safety type manual Foldable stock Caliber: .177 HandK Airgun 400 fps semi-automatic action High capacity 40-shot clip Capacity: 40-shot