The level of receptacle. Setting this object to value invalid(2) has the effect of invalidating the corresponding entry in the upsmgReceptaclesTable. It is an implementation-specific matter as to wether the agent removes an invalidated entry from the table. Accordingly, management stations must be prepared to receive tabular information from agents that corresponds to entry not currently in use. Proper interpretation of such entries requires examination of the relevant receptacleLevel object. Values 1 and 4 are reserved, value 3 is used to identify a simple one-level receptacle, and values greater than 4 represent a group of equivalent receptacles.