Polymer receiver/rifle body Built-in quick change spring system High-strength full metal gearbox 8mm metal bushings Integrated top and side rails Flip-up front and rear sight Functional bolt & spring tension release Handguard fits 8.4V and 9.6V mini and butterfly batteriesSpecifications: Operation Electric AutomaticBuild ABS polymer ReceiverFiring Modes Semi-automatic and Full-automatic, w/ Functional SafetyMuzzle Velocity 350-380 FPS (w/ 0.20g BBs)Magazine 300rd High Capacity (gear wind-up)Gearbox Version 2 (Metal)Battery Type 8.4V MiniInner Barrel Length 408 mmHop-Up AdjustableWeight 5 poundsOverall Length 27 in. Rifle