Set of Four New Production TubesThe 12AX7 Tungsol has high gain, ultralow microphonics and superb linearity. The sound of this tube is full and musical. Highly recommended for preamp V1 and V2 tubes or audiophile applications. The Tung-Sol name and trademark have been acquired by the New Sensor Corporation. This new production Tungsol tube is manufactured in Saratov, Russia. New Sensor is an American corporation and since taking ownership of this factory has been steadily improving the quality of current production tubes.Factory NEW In Box. From Russia with Love, Hurry while supplies last!