EP-5 is an Echoplex preamplifier equivalent. It sweetens and fattens up your signal. Switch left for a glassy boost, switch center for a mellow boost, and switch right to make it extra thick and heavy.
Uses standard 9V to 12V center negative power. An internal charge pump will double it to 18V to 24V. No battery clip.
EP-5 will come with a mystery knob attached.