Great, lower priced, alternative to the Tung Sol 5881s. Some people actually prefer these. Great in Fender Tweed style amps and later amps with plate voltage of 450V or lower. These will break up sooner than 6L6GCs.
NOS examples are very expensive, so this is a great way to get in on the TONE! The bases are various shades of brown and may not match. These have a mixture of different brand names including, Tung Sol, RCA, GE, Philips, CBS, etc. All are identical and made by Tung Sol. Matched pairs may comprise 2 different brands. First priority is electrical matching. Add $10 per pair if you require matching brand names on your pair.
These work great in old Fenders requiring 5881's or 6L6's. Good substitute in 6L6GC amps where less headroom (breakup at lower volumes) is desired. Also make great replacements in Fender Deluxe's where more clean headroom is desired. Just plug into your Deluxe and re-bias, no circuit changes required. Excellent choice for most 6L6GC amps if you'd like a little less clean headroom. These hold up well in amps with plate voltage up to 470 volts.
Perfect in Bassmans, Vibroluxes, Pro Reverbs, UniValves, BiValves, Emery Super Babys, and most new production Fender amps.