# Mouse2

> Middle mouse button (or third button).

## Definition

* **Type:** Field
* **Namespace:** [UnityEngine](/engine/6000.7/script-reference/unityengine.md)
* **Assembly:** UnityEngine.CoreModule

```csharp
Mouse2 = 325
```

### Remarks

Use this to detect middle mouse button presses. The “2” mouse button is the third button on the user’s mouse, which is usually the middle mouse button (often a clickable scroll wheel). Unity defines this as the "2" mouse button, as the mouse button numbering begins at 0.