The invention relates to a device for the application of a liquid medium onto at least one side of a moving material web, specifically a cardboard web; comprising at least one roll (1; 1a) that supports the web (3) and at least one feed device (5; 5a) for the coating medium, whereby during operation of the device a liquid sump (6; 6a) forms between the roll (1; 1a) and the web (3). According to the invention, the nozzle lips (13, 14; 13a, 14a) of a nozzle body (12, 12a) of the feed device (5, 5a) are configured so that the desired dimension of the open surface of the sump (6, 6a) and the depth of immersion of the nozzle lips (13, 14; 13a, 14a), and thereby the level (P) of the sump (6, 6a) are adjustable. The nozzle lips are surrounded to 80% of their total lengthnullstarting from the nozzle opening (15, 15a)nullby the sump (6, 6a).