New arrive Digital Millivolts Pen-type ORP Tester Meter Oxidation Reduction tester Potential tester      For this ORP TESTER, it does not includes calibration liquid,the one you get maybe not accurate,In order to ensure the accuracy of this item pls make  calibration when you get the parcel                    Product Description                       This handy ORP tester measure the amount of Oxidation Reduction Potential (mV) from -1999~1999mV. It has clear LCD with backlight function for convenient opearation even in dark areas.                        This device is commonly used in measurement of Water Disinfection, the stronger the ORP, the faster the microbe is killed. Oxidation Reduction Potential (ORP) was found to be a reliable indicator of bacteriological water quality.                                    Features                                   It has protective cap that helps reduce contamination            Clear LCD with backlight function            Provides instant display of measured value            Compact pensize and light weight for mobility            With CE RoHS Marking, passed & comply with all the necessary health and safety required standards set by the European Directives                                    Specifications                       Range: -1999~1999mV            Resolution: 1mV            Accuracy: ±5mV            LCD Display : 4 Digits            Battery: 4 x 1.5V (AG-13)            Operating Temperature: 0~50°C            Calibration : manual by mini screwdriver (included)            Item Color: Red            Dimension: 151 x 33 x 20mm            Weight: 53g            Battery: 4 x 1.5V (AG-13) Battery    (not include)               Package Details            1 x Digital Pentype ORP Meter  1 x Mini screwdriver / trimmer   1 x English Instruction Manual      Note: this item come without retail box.       2., this item we have two colors, we will send out them in random, thanks