Full metal slide and polymer frame, is easily upgrade-able with Tokyo Marui spec gearbox internal components Reinforced metal AEP gearbox w/ MOSFET & high performance motor Heavy weight robust construction with full metal slide, magazine, selectors, inner barrel Adjustable Hop-up and Precision bore inner barrel and high performance motor Detachable magazine and on-frame ambidextrous magazine release Includes upgraded Lipo battery and charger