The 6AH6 is a 7-pin miniature sharp-cutoff pentode engineered for high-frequency video amplifiers, wideband IF stages, and RF amplifiers operating up to 400 MHz. Featuring very high transconductance (9.0 mA/V) and dual cathode pin connections to reduce input loading at high frequencies, it was widely used in post-war television receivers, radar systems, and communications equipment. Operates on a 6.3V heater and fits standard 7-pin miniature sockets. Available NOS and tested used.