The Chris Broderick Signature SP-1 is the same SP-1 that"s used by many guitarists worldwide, but in Chris"s signature white finish. The SP-1 started it all for Mission Engineering. It features two 1/4" output jacks - one for the expression pedal and one for the switch. The switch is operated by pushing down on the front with your foot in the same way as a traditional wah pedal. This is used to turn a pedal driven effect such as a wah or vibrato on an off at the pedal itself.