The KK2.1.5 is the next big evolution of the first generation KK flight control boards. The KK2.1.5 was engineered from the ground up to bring multi-rotor flight to everyone, not just the experts. The LCD screen and built-in software make install and setup easier than ever. A host of multi-rotor craft types are pre-installed, simply select your craft type, check motor layout/propeller direction, calibrate your ESCs and radio and youre ready to go! All of which is done with easy to follow on-screen prompts. KK2.1.5 is packing newfound power with updated sensors, memory and header pins.