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# outerRadius

The radius of the tube’s outer circular cross section. Animatable.

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

## Discussion

The tube is centered in its local coordinate system. For example, a tube whose outer radius is  `5.0` extends from `-5.0` to `5.0` along the x- and z-axes. The default outer radius is `0.5`.

An outer radius of zero or less, or equal to or smaller than the inner 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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