ESky Dauphin CoAxial RC Helicopter with 2.4 GHz Radio - 13-1/2" main rotors, 15-3/4" long, weighs 8 oz. The two rotors are co-axial and counter-rotating on a single shaft. This counteracts torque, making the helicopter very easy to fly. No prior helicopter piloting experience is necessary to be successful. The helicopter is complete and ready to fly right out of the box: no gluing or soldering required. It includes a 4-channel 2.4 GHz transmitter allowing you to fly with other pilots at the same time, no matter what channel they are on. Also includes a 4-in-1 mixer/controller (electronic gyro, mixer, motor controller, receiver), two motors, two digital servos, 2-cell 7.4V 800 mAh Lithium battery and Lithium battery balance charger. Dauphin even has a LED tail strobe light for scale looks. Charge the flight battery, install 8 AA batteries in the transmitter and fly it. Durable design bounces rather than breaks in most crashes. Comes with a spare set of main rotor blades. We stock many spare parts. Instruction booklet provides some helpful tips about the basics of radio controlled helicopter flying.