Mullard KB/D CV4004 ECC83 M8137 Box Plate Valve Tube NOS 641 R7I2 J20
Mullard KB/D CV4004 ECC83 M8137 Box Plate Valve Tube NOS 641 R7I2 (J20) Code 641 R7I2 Mitcham 1967 Hickok 1-117-B test 1600/1700 mhos gm.
Mullard KB/D CV4004 ECC83 M8137 Box Plate Valve Tube NOS 641 R7I2 (J20) Code 641 R7I2 Mitcham 1967 Hickok 1-117-B test 1600/1700 mhos gm.