Specifications:Length: 850mmHeight: 310mmMain Blade Length: 425mmMain Rotor Diameter: 970mmTail Rotor Diameter: 200mmMotor Drive Gear: 12T/13TMain Drive Gear: 162TAutorotation Tail Drive Gear: 145TTail Drive Gear: 31TDrive Gear Ratio: 1:13.5:4.68/1:12.46:4.68Weight(w/o power system): 935gFlying Weight: Approx 1700gRadio transmitter and electronic equipment required for assembly:Transmitter(6-channel or more, helicopter system)Receiver(6-channel or more)Mini servo (3)Head lock gyroSpecialized Tail ServoPitch gauge60A Brushless ESC500 size Brushless motor (1600KV)22.2V 6S Li-Poly 2100~2500mAh battery425mm main blade