The Flight Controller ( FLC) is what does all the computing to keep you drone in the air. Without it you simply would not be able to fly a drone. FLC's have come in leaps and bounds in the last few years and BespokeRotors have been there from the beginning....which was the Naze 32 and Mutli Wee !! These days the flight controllers are much more advances and offer much better and easier flying experience. Like the rest of our electronics we buy direct from supplier so our FLC's are genuine.