Rc helicopter applications indoor outdoor type of model rtf ready to fly propulsion electric maximum speed 40 kmh special features flybarless remote control included transmission mode radio number of channels 6 frequency range 2400 mhz maximum operating time 10 minutes type of battery lipo battery voltage 37 v battery capacity 300 mah weight 52 g length 220 mm height 80 mm rotor diameter 241 mm skill level easy colour red