i guessin a nut shell I bought all the recommended parts, I soldered all the connections, I tested everything I replaced anything that didnt work properly, I even bought a kk5.5 flight controller, a kk2.1 controller, a apm 10 f controller at least 12 speed controllers and 15 motors cuz some didnt spin correctly, broke like 15 props, 2 transmitters, im stuck and discusted.........