Type: 1 piece RC Motor Servo Tester, used to test analog and digital servos and control the ESC. Manual mode: turn the knob to view the servo response speed. Neutral mode: making the servo go back to the neutral point. Automatic "wiper" mode: making the servo swing at the biggest angle. Function: Can convenient to detect and set the virtual, jitter and neutral of the servo. Feature: Can connect groups servos or electronic speed controller, good single chip microcomputer control, good stability, high precision. Rotate the knob to detect servo. Connect electronic speed controller (DC/EC), can get rid of the remote control equipment for manual speed regulation. Used for testing the performance of regulator and motor, no more tedious connection of remote controller and receiver.