# UseSecondaryVersion(ref AtomicSafetyHandle)

> Switches the AtomicSafetyHandle to the secondary version number.

## Definition

* **Type:** Method
* **Namespace:** [Unity.Collections.LowLevel.Unsafe](/engine/6000.5/script-reference/unity/collections/lowlevel/unsafe.md)
* **Assembly:** UnityEngine.CoreModule

## UseSecondaryVersion(AtomicSafetyHandle)

```csharp
public static void UseSecondaryVersion(ref AtomicSafetyHandle handle)
```

### Parameters

**** (\[AtomicSafetyHandle]\(/engine/6000.5/script-reference/unity/collections/lowlevel/unsafe/atomicsafetyhandle)): The AtomicSafetyHandle to switch.

### Remarks

For a conceptual overview of container version numbers, refer to [Copying NativeContainer structures](/engine/6000.5/manual/scripting/optimization/job-system/thread-safe-types/copy-nativecontainer.md).