Fender?s EXP-1 Expression Pedal is a dynamic new dual-modedigital pedal that controls the volume or amp/effect parameters onMustang? III, IV and V amplifiers and on the new Mustang Floormulti-effects unit. Switch between ?Volume? and ?Expression?modes by stepping on the toe end of the pedal. Red and greenLEDs indicate the mode in use.In ?Volume? mode-indicated by illumination of the greenLED-EXP-1 controls the master volume or can be turned off. In?Expression? mode-indicated by illumination of the red LED-theEXP-1 controls most Mustang amp and effects parameters.Common among these, for example, are the frequency parametersof a wah effect and the rate/time parameters of modulation anddelay effects.The EXP-1 pedal puts great tonal control at your feet andprovides a great way to make your Mustang amp or multi-effectsunit even more fun, more expressive and more versatile.