The R/C radio controls the throttle and the direction that the quadcopter travels. When choosing an R/C radio, the most important feature is how many channels the radio supports. One channel independently controls one servo or ESC. The more channels, the more devices that can be independently controlled. The minimum number of channels for a quadcopter is 5. Four of those channels are for the four motors and the other channel for switching between flight modes. These flight modes could be switching from stable or acrobat mode or to enable or disable autonomous flying. A radio with more than 5 channels will allow auxiliary devices to be controlled. Some devices that could be controlled are lights, robotic cameras or landing gear.