Behringer DC9 Dynamics Compressor Pedal Kick ass with a powerful, percussive sound on your clean guitar and melt steel alloy when playing lead with ultimate sustain "Smoothes out" volume peaks and provides endless sustain with ultra-stable dynamics Blue status LED for effect on/off and battery check True hard-wire bypass for ultimate signal inte Runs on 9 V battery or the BEHRINGER PSU-SB DC power supply (not included)