A chassis contains a number of physical entities such as power supplies and cards. Each physical entity resides at some location. A chassis can contain a number of types of location. Each type of location is specialised to a different purpose. Currently there are four types of location defined. This list can be extended for a particular application:

modular-slot: A location of this type can take a number of different entities. They are general purpose and are often the purpose of the device. power-supply-bay: Locations of this type can only contain an instance of a power supply. fan-position: This location can only hold a fan. backplane-position: A position of this type can only contain a backplane.