These 6V6GT / G = VT-107A (US military type) SYLVANIA, absolutely original made in USA, as a Beam Power Tetrode are considered among the best ever produced. Very high quality "military standard" which is reflected in a great AUDIO performance as amplifiers. Gorgeous pair completely MATCHED, SAME codes: SC966A. not to be missed!
EQUIVALENT: 6V6GT = CV509 = ZA5306 = 10E / 349 = VT196_GPO 6П6С = 6V6 = CV510 = CV511 = VT-107A & SUBSTITUTE: OSW3106 = 5871 = 6V6GTY = 7184 = 7408 = 6P6P = 6V6EG