For prefabs in a scene we can add the ConvertToEntity and PhysicsShapeAuthoring components to convert a static mesh with collider to an entity with a physicscollider. However, if I'm converting a prefab in code then instantiating entities at runtime, how do I convert the collider to a physicscollider? Here is what I'm currently doing (without Unity.Physics) - this all works fine. Code (CSharp): Entity prefabEntity = GameObjectConversionUtility.ConvertGameObjectHierarchy(prefabs[i].gameObject, conversionSettings); .. EntityArchetype entityArcheType = world.EntityManager.CreateArchetype(archetypeComponentTypeArray); .. world.GetOrCreateSystem<MySystem>(); // create x entities from prefab in a loop .. Entity entity = entityManager.Instantiate(prefabEntity); // Add components .. // SetComponentData .. I'm aware of PhysicsShapeAuthoring component but that seems to require a ConvertToEntity component which doesn't seem to fit my scenario. I "could" create a new PhysicsCollider and add it as a component but what I really want is to convert the existing collider to a PhysicsCollider.