The invention relates to a device for automatic dispensing of a maintenance agent, such as an anti-icing agent or a de-icing agent, on specific parts of a rolling stock travelling on a railway track. The device comprises a dispensing unit, a detection unit configured to generate a detection signal before said rolling stock reaches the dispensing unit, a sensor unit configured to determine position and velocity of the rolling stock, and a control unit. The control unit is configured to receive said detection signal from said detection unit, determine a dispensing schedule based on said rolling-stock velocity, and transmit a control signal to the dispensing unit to control said dispensing unit based on said dispensing schedule. Furthermore, the present inventive concept also relates to an associated method.