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 and 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 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.
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.

RC Parts & Accs: Servo Accessories
For Vehicle Type: Helicopters
Material: Plastic
Voltage consumption: DC4.8-6V
Color: Blue
Item size: 46x32x23mm

1 x Multi Servo Tester