Most standard radio control (RC) servos have three wires, each a different color. Usually, they are either black, red, and white, or they are brown, red, and orange/yellow:

• brown or black = ground (GND, battery negative terminal)
• red = servo power (Vservo, battery positive terminal)
• orange, yellow, white, or blue = servo control signal line

Please check the specs for your servo to determine the proper power supply voltage, and please take care to plug the servo into your device in the proper orientation (plugging it in backwards could break the servo or your device).

Note: Some of the servos we carry also have an optional fourth green wire that is separate from the three standard ones. This wire provides access to the feedback potentiometer, allowing you to directly measure the position of the output. The servos with this extra wire have "with Position Feedback" at the ends of their product names. The picture below is an example of such a servo.

FEETECH Sub-Micro Servo FS0403-FB with Position Feedback.