An agricultural baler for compressing square straw bales, comprising: - at least one torque connection, - at least one transmission shaft, - at least one flywheel, - at least one activating mechanism, - at least one compressing means, as well as - at least one compressing channel, wherein, by means of the torque connection, a torque transmitting connection can be established between the baler and a drive shaft of a drive unit which drives the baler, wherein, by means of the transmission shaft, a torque which is taken up by means of the torque connection can be transmitted in the direction of the flywheel, wherein a torque of the flywheel can be transmitted by means of the activating mechanism to the compressing means in a manner such that the compressing means can be oscillated backwards and forwards inside the compressing channel and in this manner, material which is present in the compressing channel can be successively compressed, a transmission device which comprises at least two gear settings being disposed between the flywheel and the torque connection, wherein the gear settings have different transmission ratios, characterized in that the baler comprises a control unit by means of which the transmission device can be shifted automatically between its gear settings and the baler comprises an actuator by means of which a clutch of the transmission device can be shifted between the gear settings, wherein the control unit is connected by means of a data line to the actuator which acts on a gear lever of the clutch so that the actuator actuates a sliding sleeve of the clutch between the first and the second clutch positions. - at least one torque connection, - at least one transmission shaft, - at least one flywheel, - at least one activating mechanism, - at least one compressing means, as well as - at least one compressing channel, wherein, by means of the torque connection, a torque transmitting connection can be established between the baler and a drive shaft of a drive unit which drives the baler, wherein, by means of the transmission shaft, a torque which is taken up by means of the torque connection can be transmitted in the direction of the flywheel, wherein a torque of the flywheel can be transmitted by means of the activating mechanism to the compressing means in a manner such that the compressing means can be oscillated backwards and forwards inside the compressing channel and in this manner, material which is present in the compressing channel can be successively compressed, a transmission device which comprises at least two gear settings being disposed between the flywheel and the torque connection, wherein the gear settings have different transmission ratios, characterized in that the baler comprises a control unit by means of which the transmission device can be shifted automatically between its gear settings and the baler comprises an actuator by means of which a clutch of the transmission device can be shifted between the gear settings, wherein the control unit is connected by means of a data line to the actuator which acts on a gear lever of the clutch so that the actuator actuates a sliding sleeve of the clutch between the first and the second clutch positions.