A device for variably adjusting control times of gas exchange valves of an internal combustion engine. The device has a drive element, an output element, a rotation angle limiting device and a control valve and counter-working pressure chambers are also provided. Phase adjustment between the output and drive element is initiated by applying pressure to one pressure chamber while discharging the other pressure chamber. The rotation angle limiting device can be locked or unlocked to prevent or allow phasing. The control valve has a valve housing and a control piston. An inflow connection, an outflow connection, a control connection and two working connections are embodied on the valve housing.