The Classic Army Box Mag for the M249 functions the exact same way the Top version does. It has an auto winding feature with a button at the bottom of the mag and is powered by a single 9volt battery. Press the button to wind the mag and then fire! This magazine is recommended for use with Classic Army M249 guns only. These magazines may work with other brands but they cannot be guaranteed by Airsoft GI.
M249 AEG High Capacity Box Magazine
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