Electro-Harmonix Clockworks Electronic Drum Controller Works as a master clock for sequencers and drum machines Generates pulses to trigger devices like electronic percussion products Connect up to four devices to the four separate clock channels driven from the same master clock. Creating polyrhythms is fun and easy Fully Analog. Master clock can be generated internally by the Clockworks or come from an outside source Supplied with an EHX 18VDC/500 mA AC Adapter.