Overview: The device also can be used as a signal generator for electric speed controller (ESC), then you can test your motor system without using a transmitter & receiver. There are 3 modes to check servos or ESC: Manual mode: turn the knob with different speed, check the reaction time. Neutral mode: make the servo go back to the neutral point. Automatic "window wiper" mode: make the servo swing like a window wipers in the biggest angle. It can connect 1-3 servos simultaneously & test such as 1-3 servos consistency & so on. You can also connect 1-3 ESC to test & compare their reaction time respectively. It can connect 3 servos of the CCPM helicopters & select servos. It can also connect the servo of airplanes install the steering-box & adjust planes by using such as the neutral mode & so on. Specification: Voltage consumption: DC4.8-6V Weight Approx:8g Size Approx:10 x 5 x 2