12SN7GTA GE NOS 1961 (8.4/8.4ma)
12SN7GTA RCA coin-base branded GE NOS 1980 (12.2/12.2ma) 1-2% section balance
12SN7GTA Westinghouse black plates "O" getter NOS 1961 (9.0/9.8ma)
12SN7GTA Westinghouse gray plates "O" getter NOS 1964 (7.6/8.0ma)