Abstract: A drive is proposed for adjusting flaps, in particular flaps for supplying air in automotive vehicles, the drive having a drive motor received in a housing and a step-down gear. The housing comprises three housing parts, the second housing part having, on its one upper side, a receiving recess for insertion of the transmission parts from above and, on its other opposite lower side, a cavity for insertion of the drive motor from below. The transmission parts are fixed by a first housing part which is clipped to the second housing part and the drive motor is covered by a third housing part which is likewise clipped to the second housing part.