The TUNG SOL 35C5 tube is a vintage audio component sought after by collectors and enthusiasts for its unique characteristics and nostalgic appeal. This true NOS (new old stock) tube comes in its original nie sulphide coating, adding to its authenticity and desirability. Made in the United States, this model is a single bulb design that is a suitable sub for a 35C5 tube, offering a touch of vintage charm to any audio setup.