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# innerRadius

The radius of the circular hole through the tube. Animatable.

```
var innerRadius: CGFloat { get set }
```

## Discussion

The tube is centered in its local coordinate system. For example, if a tube has an inner radius of `1.0`, the cylindrical hole through its center extends from `-0.5` to `0.5` along the x- and z-axes. The default inner radius is `0.25`.

An inner radius of zero or less, or equal to or greater than the outer radius, creates an empty geometry.

You can animate changes to this property’s value. See [Animating SceneKit Content](/documentation/SceneKit/animating-scenekit-content).

---

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