Abstract: A device for applying viscous material to workpieces includes a rotary lance in a holder apparatus and rotatable about a longitudinally-extending rotation axis, the lance having at least one material outlet. A needle valve associated with each material outlet has a longitudinally-extending valve needle used to close each material outlet on a valve seat. Each valve needle has an associated cylinder with a plunger chamber in which a plunger is movable by pressure applied by a fluid, the valve needle being permanently connected to the plunger. A tappet is connected to each plunger, the tappet, at its upper end facing away from the at least one valve seat, being sealingly guided out of the associated plunger chamber. The rotary lance has a measuring element which can be acted upon by the tappet and moved longitudinally; and the holder apparatus has a sensor for determining the measuring element position.