The MP44 Airsoft Gun is an exquisite time period AEG. The quality of materials and attention to detail are bringing MP44 to the top of the market. The battery is stored in the stock for balance and realism. The functioning charging handle is powered by a stiff spring that gives off a very satisfying 'clack' when pulled back and released. There is no better choice for reenactors and WWII buffs than this Sturmgewehr MP44. Full Metal Constructed with Real Wood Fixed Stock Fully/Semi Automatic Shooting Mode AEG Steel Gears Metal Gear Box Adjustable Spin UP Shooting System Velocity: 420-440 w/.20g BBs Please only use .20 and 0.25 gram high quality BBs with MP44 to keep it in working conditions.