Umarex Canex .177 Caliber CO2 Air Rifle Chambered in .177 Cal Uses two 12-gram CO2 cartridges Fresh cartridges last for about 45 shots Semi-Automatic action 3-10 round auto index magazines Lightweight polymer stock Weight: 3.5lbs Overall Length: 39.4" Barrel length: 22.83" Length of pull: 14.17" Fixed front sight, adjustable rear sight 11mm dovetail optic mount Muzzle velocity: 600 FPS with lead, 800 FPS with alloy