Disclosed is a device (1) for cooling metal sheets and strips during the production thereof, particularly following rolling thereof. Said device (1) comprises a feeding duct (2) for delivering a cooling medium, especially water. Said feeding duct (2) is connected to a housing (3) inside which two nozzle rails (4, 5) are disposed so as to be movable relative to one another. Said two nozzle rails (4, 5) can be arranged at a short distance (a) from each other, thereby forming a nozzle gap (6) for the cooling medium, said nozzle gap (6) having a rectangular cross section. At least one element (8) that forms a barrier for the cooling medium is placed in the housing (3) between the point of entrance (7) of the cooling medium into the housing (3) and the nozzle gap (6).