The Saturnworks expression pedal provides compact expression capability for Boss effects and is functionally similar to the Roland EV-5 and EV-7. Each pedal is individually hand crafted with quality components including a heavy duty Neutrik jack, an Alpha potentiometer, a rugged Hammond-type cast aluminum case, an 'MXR' type knob, and a (removable) Dunlop rubber knob to make the pedal easier to adjust with your foot. This pedal provides expression capability for pedals that utilize stereo (TRS) expression pedals. Please refer to your pedal's owners manual to determine whether your pedal uses a stereo or mono expression pedal. If you have any doubts regarding the suitability of your particular pedal, please contact me before bidding. This expression pedal is passive and does not require an AC adapter or battery. At 3.5"x1.5"x1.25", it is also extremely compact as to not clutter up your pedal board.