Following the tradition of the Dallas Rangemaster, which has been used by guitarists like Tony Iommi, Brian May, and Glen Tipton, the Catalinbread Naga Viper boosts tube amps into that juicy, sought-after rock tone. The Naga Viper is Catalinbread's enhanced version of the famous Rangemaster circuit with an additional two controls: Range and Heat. Range allows you to go anywhere from a classic treble-boost to a full-range boost, while the Heat knob controls gain level. This pedal allows you to dial in the exact frequencies you want boosted and really saturates the front-end of any tube amp.