Boss BC-1X - Bass Compressor ControlsPedal switchTHRESHOLD knobRATIO knobRELEASE knobLEVEL knobIndicatorCHECK indicator (Serves also as battery check indicator)GAIN REDUCTION indicatorConnectorsINPUT jackOUTPUT jackDC IN jackPower SupplyAlkaline battery (9V, 6LR61) or Carbon-zinc battery (9V, 6F22)AC adaptor (sold separately)Working Voltage:&nbsp;18 VCurrent Draw:&nbsp;90 mAExpected battery life under continuous use (These figures will vary depending on the actual conditions of use.):&nbsp;Alkaline: Approx. 3 hoursDimension