Electro-Harmonix Crash Pad Analog Drum Synth Creates a range of percussive sounds from cymbals, snares and hi hats to sweeps Triggers via the on-board pushbutton, an external (non-MIDI) drum pad and most clock generators Process external sounds thru the resonant filter + EXP/CV input for real-time filter control Supplied with an EHX9.6DC-200 PSU, also accepts a 9V battery Works great with the EHX Clockworks Rhythm Generator/Synthesizer, 8 Step Program Analog Expression/CV Sequencer and other similar devices