This 2-in-1 pH & ORP controller and monitor simultaneously measures and displays both pH value and redox value (ORP) It comes with 2 BNC electrodes (pH and redox) and 2 output power sockets Both electrodes are detachable, they can be replaced easily at any time As for the relay output power sockets, you can plug in your own device to it, e g air outlet stone, O3 ozoniser, oxygen pump, CO2-regulator, electromagnetic valve and other ORP & pH control devices Simply set the desired Hi/ Low pH/redox values in the controller It will turn on your device if the currently measured pH or Redox value is lower than your set value, and it will turn off your device if the measured value is higher than your set value Measuring rangePH: 0 00 ~ 14 00pHORP: -1999 ~ 1999mVAccuracyPH: plusmn0 1%+0 02PHORP: plusmn5mVResolutionPH: 0 01pHORP: 1mVSet RangePH: 3 50 ~ 10 50pHORP: -500 ~ 500mVRelay Contact: 5A for AC 110V or 220VEnvironmentOperation Temperature : 0 to 50 degC (32 to 122 degF)Ambient Humidity : 90 or less than 90 % R H Power Requirement : AC110V plusmn10% 60Hz / AC220V plusmn10% 50HzPower Consumption : 2 WattsVoltage: AC100-240VPlug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so oncolor:BlueMaterial:composite materialPackage Contents:1 x 2-in-1 pH & ORP controller and monitorOnly the above package content, other products are not included Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing The measurement allowed error is +/- 1-3cm