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A medium-output power tube (generally 20-25 watts) often used in Fender(R) professional amplifiers including the Bassman(R), Bandmaster(R), Concert, Dual Showman(R), Hot Rod(TM) Series, Pro Series, Super Reverb(R), Tremolux(TM), Twin, Vibrolux(R), Super-Sonic(TM), Blues Deluxe(TM), Blues DeVille(TM) and others. Available in many variations, its response is round, with a pronounced midrange character; strident and chesty with a super-bright and clean, powerful punch. Perhaps the most recognized signature tone for U.S. guitar music of all styles from the '60s onward.