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; It can connect 1-3 servos simultaneously and test such as 1-3 servos consistency and so on. You can also connect 1-3 ESC to test and compare their reaction time respectively. Automatic "window wiper" mode: make the servo swing like a window wipers in the biggest angle. It can connect 3 servos of the CCPM helicopters and select servos. It can also connect the servo of airplanes install the steering-box and adjust planes by using such as the neutral mode and so on., Weight: 0.01873929227 Pounds, Manufacturer: Tuidzljd