Answer:
A float switch
Step-by-step explanation:
A float switch is a component of a wet-dry vacuum cleaner that is not present in a typical canister style residential cleaner.
A float switch is a device used to detect the level of liquid within a wet-dry vacuum cleaner. The switch may be used as an indicator to control other devices.
Some float switches contain a two-stage switch. The associated pump is activated as the liquid rises to the trigger point of the first stage. The second stage will be triggered if the liquid continues to rises.