Airsoft GI Classic Army Black M249 AEG High Capacity Box Magazine, Holds 2,400 Rounds &ndash; Power Auto Winding Box Magazine Runs from Battery  You will power this Automatic Electric Gun box magazine with a 9-volt battery Simple Operation  To wind the 2,400-capacity mag, youll just press a button and then fire High Quality Construction  The large box magazine consists of an ABS plastic material, ensuring a long lifespan Designed for Classic Army M249 Guns  Although this box magazine may fit other brands of guns, our high capacity box mag is only guaranteed to work with the M249 from Classic Army Ammo to Burn  A 2,400-round capacity will ensure that you never run out of ammo