A coupling device for connecting a water powered apparatus to a faucet having a mouth (1) to which a cylindrical aerator housing (3), has an aerator (2) and an attachment (4) of water powered apparatus. The aerator (2) has an upper cylindrical portion (12) and a lower cylindrical portion (15) that are joined together by converging arms (14) between which the ventilation openings (16) are formed for aerating flowing water. The attachment (4) of water powered apparatus is provided with connecting means for coupling with engagement means not integral with the aerator cylindrical housing (3).
