6Н8С - low frequency double triode, direct substitute for 6SN7. New old stock. New in original boxes. Produced in 1979, NEVZ (Novosibirsk).
Perfect choice for clean channel of mic/guitar preamps or hi-fi/hi-end.
Many people says that 6N8S (6SN7), 6N9S (6SL7) has a better sounding tone than noval twin triodes like 12AX7 (ECC83).
If you've never heard this Russian tube it's time to give it a chance. This tube is cheap but it worth more than it's price.