Product Description: 1. The swimming pool water is between 6.5-8ph, the ORP is between 487-840mv, and the chlorine value will be displayed normally. Chlorine will not be displayed if either value is out of range 2. If the PH value is lower than 6.5, it means that the water quality is too acidic and there are too many impurities. 3. If the ORP value is above 850mv, it means that too many disinfectants are added, and it is necessary to add water or change the water for neutralization. 4. Only supports testing swimming pool water quality. Specification: PH range: 0.1-14.0 Resolution: 0.1ph Accuracy: 0.1ph Temperature range: 0.1-80.0 31.2-176 Resolution: 0.1/0.1 Accuracy: 0.5 EC range: 0-1999us/cm , 10.01- 20.0mS/cm , 2000-10000uS/cm Resolution: 1uS/cm 10uS/cm 0.01mS/CM Accuracy: 2% FS TDS range: 0-999ppm, 1000-9990ppt Resolution: 1ppm 10ppm Accuracy: 2% FS CL range: 0.1-4.0mg/L Resolution: 0.1mg/L ORP range: 999mv Resolution: 1mv Accuracy: 15mv Battery: 3*AAA, not included Size: about 160*80*26mm, 220g Display: LCD digital display Backlight: APP control Temperature: Automatic temperature compensation 0-60 Operating Environment: 0.1-80; Relative Humidity: Maximum 90% pH Calibration: pH: 6.86/4.00/9.18 or 7.00/4.00/10.01 Packing List: 6-in-1 water quality pen*1 (battery not included)