1、Special designed for racing quadcopter 2、Small size and lightweight, which can be installed on anywhere of the drone body 3、Supporting for Oneshot125, the common throttle signal can up to 500Hz with faster refresh speed, with high speed and can compatible with various flight-control system. 6. Supporting for 4S battery which can meet different needs 4、The signal line adopts twisted pair of silicone wire, can reduce the interference generated by transmission of signals within the copper to ensure stable flying 5、4 layers board circuit design, with exquisite workmanship and stable performance Features: 1. Special designed for racing quadcopter. 2. Small size and lightweight, which can be installed on anywhere of the drone body. 3. F390 main control chip, imported Mos chip combine with 3 in 1 IC drive, which has high efficiency and high reaction speed. 4. Supporting for Damped Light to make the motor slow down quickly and the battery will recover to extend the flying time. High efficiency and low consumption, the speed controller will not self-heating while standby. 5. Supporting for Oneshot125, the common throttle signal can up to 500Hz with faster refresh speed, with high speed and can compatible with various flight-control system. 6. Supporting for 4S battery which can meet different needs. 7. Supporting for BLHli refresh and can easily upgrade via the signal line. 8. The signal line adopts twisted pair of silicone wire, can reduce the interference generated by transmission of signals within the copper to ensure stable flying. 9. 4 layers board circuit design, with exquisite workmanship and stable performance. Specification: Condition: 100% Brand New Item Type: RC Accessory Optional Quantity:1PC, 4PCS Continuous Current: 30A Burst Current: 40A Input voltage: 2-4S Size: Approx. 29 * 12 * 5mm / 1.1 * 0.5 * 0.2inch Package Weight: Approx. 7g(1PC), 35g(4PCS) Package Include: 1PC / 4PCS Electronic Speed Controller