An excellent way to recharge the tube amplifier in your guitar rig. Sovtek/Electro Harmonix EL84 (EL84EH) offers newfound power to give new life to your amplifier. A perfect replacement tube for VOX AC30, Peavey Classic 30 and Fender Blues Junior guitar amplifiers, the EL84EH power pentode from Sovtek/Electro Harmonix is a trusted tube that will keep your tube amplifier fired up from performance to performance.