(!!!) (BEST PAIR) 7247=12DW7 CBS gray ribbed plates NOS 1960 (1.0/10ma and 1.1/9.5ma)

1 pair) 7247=12DW7 CBS gray ribbed plates NOS 1960

1 tube) 1.0ma Gm=1500 (12AX7) and 10ma Gm=2200 (12AU7)  

1 tube) 1.1ma Gm=1500 (12AX7) and 9.5ma Gm=2100 (12AU7)  

Tested on Amplitrex

12AX7 Section NOS = 0.9ma-1.2ma and Gm=1500-1600+

12AU7 Section NOS = 8-10ma and Gm=1800-2200

Recommended for:

- Fisher 400 CX-2

- Eico 2510 amp

- Eico ST-70 preamp 1961

- Ampeg SVT 1974, VT40