Air outlet, in particular for a vehicle

The vent has a central module (4) including a plug cap (21) with a lip, a star wheel (22) and a cartridge (25) that is inserted through a hole of a wall of an instrument panel, into a container (37). The wheel is activated to bring the cartridge either in perfume diffusion/non diffusion position, or in intermediate position. The lip strengthens sealing of the container with respect to an air flow duct in air non-diffusion position.