# Physics Low Level Settings 2D asset Inspector window reference

> Explore the properties you can use to configure the global settings of the LowLevelPhysics2D API in the Editor.

> **Note:**
>
> This documentation is about writing C# scripts using the `LowLevelPhysics2D` API. To use 2D physics in the Unity Editor using components like the Rigidbody 2D component, refer to [2D physics](/engine/6000.3/manual/unity2d/2d-physics.md.md) instead.

Explore the properties and settings you can use to configure the defaults and global behaviour of the `LowLevelPhysics2D` API. For more information, refer to [Configure global 2D physics settings](/engine/6000.3/manual/unity2d/2d-physics-api/properties/global-settings.md).

## Layers

The properties in this section configure the layers Unity uses to detect collision. For more information, refer to [Configure collisions between LowLevelPhysics2D API objects](/engine/6000.3/manual/unity2d/2d-physics-api/interactions/collisions-enable.md).

| **Property**            | **Description**                                                                                                                                                                                                                                |
| ----------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Physics Layer Names** | Sets the names of the 64 layers the `PhysicsMask` API uses if you enable **Use Full Layers**. By default, the first layer has the name **Default** and the other layers have no name.                                                          |
| **Use Full Layers**     | Enables the `PhysicsMask` API using the 64 layers listed under **Physics Layer Names**. If you disable this property, the `PhysicsMask` API uses the 32 [GameObject layers](/engine/6000.3/manual/working-with-gameobjects/layers.md) instead. |

## Default Definitions

The properties in this section set the default values when you create a new definition object. For the individual sections, refer to the following:

* [World definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/world.md)
* [Body definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/body.md)
* [Shape definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/shape.md)
* [Chain definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/chain.md)
* [Distance joint definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/joint-distance.md)
* [Fixed joint definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/joint-fixed.md)
* [Hinge joint definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/joint-hinge.md)
* [Relative joint definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/joint-relative.md)
* [Slider joint definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/joint-slider.md)
* [Wheel joint definition reference](/engine/6000.3/manual/unity2d/2d-physics-api/reference/joint-wheel.md)

## Globals

| **Property**               | **Description**                                                                                                                                                                                             |
| -------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Concurrent Simulations** | Sets the number of physics simulations that can run at the same time. The default is 2.                                                                                                                     |
| **Length Units Per Meter** | Sets the number of Unity units that correspond to one meter in the physics simulation. The default is 1.                                                                                                    |
| **Draw In Build**          | Draws the debug visualization in a built application. For more information, refer to [Draw a debug visualization of objects](/engine/6000.3/manual/unity2d/2d-physics-api/create-objects/debug-drawing.md). |
| **Bypass Low Level**       | Disables the `LowLevelPhysics2D` API physics system.                                                                                                                                                        |

## Additional resources

* [Configure global 2D physics settings](/engine/6000.3/manual/unity2d/2d-physics-api/properties/global-settings.md)
* [Configure 2D physics properties using a definition](/engine/6000.3/manual/unity2d/2d-physics-api/properties/definitions.md)