Electro-Harmonix Deluxe Electric Mistress XO Guitar Flange Effect Pedal The same incredible, rich, resonant flanging now in a pedal board friendly package Unique Filter Matrix effect stops the sweep for freeze-frame tones and tricks True bypass for maximum signal path integrity The circuit remains true to its roots, but power is supplied by a 9V battery. Also works with an EHX9.6-200 AC adapter