Big pulse modulator tetrode GMI-2B (ГМИ-2Б) with massive copper anode. Maximum anode dissipation: 900W. Maximum anode voltage: 32kV. Nett weight of the tube is approximately 4,5 kg. New in box tubes and in perfect condition (please see the gallery pictures). A very nice piece to your collection, but you can also use it for a DIY project. Made in the the 80's.