Umarex Heckler & Koch HK45
The HK45 is the largest caliber pistol made by Heckler & Koch (.45 ACP). This licensed C02 powered version fires 4.5mm steel BBs from a 19 shot magazine and is made of a polymer frame with a metal slide. The non-blowback operation was chosen for this CO₂ pistol giving the shooters a system with superior accuracy and a higher number of shots by utilizing the C02 more efficiently.
12g C02 Cylinder