The present invention relates to a two-compartment aerosol device containing a hair treatment composition in a first compartment and a compressed gas chosen from air, nitrogen and carbon dioxide, and mixtures thereof, in a second compartment, where the hair treatment composition contains, in an alcoholic or aqueous-alcoholic cosmetically acceptable medium, at least one hair sheen agent and/or conditioner in a concentration of greater than 0.4% by weight relative to the total weight of the composition.