(!!!) (Single 1960) ECC83=12AX7 VALVO Germany made in Hamburg "O" getter used/good 1960 (0.9/1.0ma)

1 low noise tube) ECC83=12AX7 VALVO Germany made in Hamburg 
with slanted "O" getter halo used/good 1960 in white box

1 section) Gm=1300 (0.9ma)
1 section) Gm=1500 (1.0ma)


Good used Gm range 1300-1500+
Good used mA range 0.7-1.0mA+