The 12BA6 is a remote-cutoff pentode designed for use as a high-gain radio-frequency or intermediate-frequency amplifier. It is direct replacement for the HF93, CV1928 and 12F31 (Tesla) tubes. 6BA6 and 6F31 (Tesla) do have another heater ratings. New old stock tubes in original boxes (some of the boxes may have longer storage marks), tested. Made in the early 60's (please look at the gallery).