ELECTRO HARMONIX 7591 IN STOCK. A tough pentode found in many older guitar and HiFi amps, such as: Eico ST-40 and ST-70.
TUNG-SOL 7591A Made in Russia. Fresh stock 2019 manufacture. Order one for single = 1 Valve Order two for matched pair = 2 Valves Order four for matched quad = 4 Valves