Get my Guitar found the latest prices on the Catalinbread Naga Viper MKII Boost.

The Naga Viper MKII Boost Pedal — Brian May, Eric Clapton, Tony Iommi, and others pioneered the use of the treble booster, more specifically the Dallas Rangemaster. One thing that made this circuit such an anomaly in effects canon was its lack of foot control; the Rangemaster was an amp-top device with a teeny-tiny toggle switch that was an absolute pain to disengage mid-riff.