Turbocharger provided with a bypass valve device comprising a valve element having a shaft movably connected to a valve element support, with a spindle between the valve element support and an adjusting lever extending transversely to the spindle, and an adjusting lever actuating element pivotably connected to the adjusting lever; an annular spring element is provided in at least one of a first position between the valve element and the valve element support and a second position between the adjusting lever and the adjusting lever actuating element, the spring element comprising at least one annular spring steel disc with a bead being configured and dimensioned so as to minimize play between the valve element and its support or between the adjusting lever and its actuating element.