The product is a lot of 4 CEI Electron Tubes 6BZ6, made in the USA by GE. These vintage electron tubes are new old stock (NOS) and have not been modified. They are ideal for vintage audio and video equipment, adding to the authenticity and quality of the system. The CEI Electron Tubes 6BZ6 are a sought-after collectible for vintage electronics enthusiasts and can enhance the performance of vintage audio equipment.