# SendContactCallbacks()

> Send all current _contactBeginEvents and _contactEndEvents where either of the PhysicsShape involved are valid (see _isValid ) and have a callback target assigned (see _callbackTarget ). Only callback targets that implement PhysicsCallbacks.IContactCallback will be called. This is called automatically every simulation step. This must be called on the main thread.

## Definition

* **Type:** Method
* **Namespace:** [Unity.U2D.Physics](/engine/6000.7/script-reference/unity/u2d/physics.md)
* **Assembly:** UnityEngine.PhysicsCore2DModule

```csharp
public void SendContactCallbacks()
```