# Bittle X

<figure><img src="https://1565080149-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-MQ6a951Q6Jn1Zzt5Ajr-887967055%2Fuploads%2FtclMSH1JifgegK78Jauv%2FBittleX0_Wire.png?alt=media&#x26;token=ffb131f7-ed63-4428-973c-7f830fab8237" alt=""><figcaption></figcaption></figure>

{% hint style="danger" %}
A servo plug has three wires. Plug it in the right direction or you may burn the chip. The color of wires may vary for different models. However, the darkest-colored (Black or Brown) wire (GND for ground) is always the GND wire as a convention. The GND wire should be plugged closest to the board.&#x20;
{% endhint %}

{% hint style="danger" %}
The index number of the joint servo has **no corresponding relationship** with the PWM pin number on the main board. **You don't even need to read the pin numbers on the PCB board.**&#x20;
{% endhint %}