NOS Mullard ECC83 (Relabeled)
One in stock labeled and boxed as Ameperex.
Original equipment in '60s Marshalls. Great in Marshalls and other British style amps. All made by Mullard with Blackburn "B" factory code, but relabeled by other major tube companies like Philips, RCA, GE, Amperex, Telefunken, etc.