# Inertial

- Source proto: `rb/api/geometry.proto`

Geometry type: inertial.

| Field | Type | Label | Description |
| ----- | ---- | ----- | ----------- |
| mass | [double](../scalar-value-types.md#scalar-value-types) |  | Mass (kg) |
| center_of_mass | [Vec3](vec3.md#rb-api-vec3) |  | Center of mass (m) |
| inertia | [Inertia](inertia.md#rb-api-inertia) |  | Inertia tensor |