The CM16 offers an entirely redesigned Polymer receiver, borrowing from the ever popular billet style that has been seen more and more in the firearms world. Other improvements include and ambidextrous magazine release, ambidextrous mock charging handle, m-lok handguard and a selector switch with a heavy duty detent that gives the user tactile feedback when changing fire modes. Installed from the factory is a MOSFET, allowing the user to use LiPo batteries without worrying about damaging the gun and a programmable fire control which allows the shooter to choose either full-auto fire , or three round burst fire modes 7.4v 1000mAh LiPo Battery and Smart Charger Included