public LayerMask includeLayers { get; set; }

The Layer Collision Matrix defines which layers can contact other layers. Use this property to specify additional layers that this specific Collider instance can contact.

NOTE: Layers can be included or excluded differently depending on the settings of each Collider instance. As such, there could be a conflicting decision for whether two Collider instances can come into contact with each other. To learn how Unity decides this, see Collider.layerOverridePriority.

Additional Resources: Collider.excludeLayers, Rigidbody.includeLayers, Rigidbody.excludeLayers, ArticulationBody.includeLayers, ArticulationBody.excludeLayers.