Features: EFM8BB21F16G MCU, makes with 50 MHz maximum operating frequency Using dedicated 3in1 drivers, the start more smooth ESC maximum speed is limited to 500k eRPM More suitable for ultra small multirotors Two layers tower structure between 4in1 ESC and FC using quick pin connection, making the installation faster and more convenient F3 flight controller, supports PPM and SBUS remote control/receiving mode FC integrated OSD, no external OSD device is required, integrated 5V/1A for image transmitter, camera, buzzer, LED and other peripheral devices BLHeli-S firmware designed for superior performance in multirotors, and uses hardware generated motor There are tuneable parameters that can make the code run well even in the most demanding situations The code supports regular 1-2ms pulse width input, as well as Oneshot125 , Oneshot42 and Multishot Supports Dshot digital signal, anti-interference ability is stronger, and do not need throttle calibration The motors are high-torque and high-efficiency CNC machined aluminum case High purity copper windings maximizes efficiency Precision engineered for maximum energy conversion