Russian double triode 6N8S (6H8C) was designed for amplification of low-frequency voltage, but its usage is really universal. It is direct replacement of the 6SN7, 6SN7GT and also 6CC10 tubes. Original service life guarantee: more than 2000 operating hours. New old stock tubes and tested. Manufacturer: Nevz, Novosibirsk. Made in the 60's and 70's.