(!!!) (Recommended Pair) 12SL7GT RCA black plates NOS 1974 (2.1/2.2ma and 2.3/2.4ma) (same Gm)

1 pair) 12SL7GT RCA NOS 1974 (ES)

1 tube) 2.1/2.2ma Gm=1500/1600

1 tube) 2.3/2.4ma Gm=1500/1600

Good ma range 1.8-2.5ma

Good Gm = 1400-1600