Function: Tests the water quality of different waters to ensure you get the best water quality and temperature (cannot test PH or value of some dissolved substances in water).Hold function: saves the measurement results for easy reading and recording.Automatic function: switches off the device after 10 minutes of non-use to save batteries.Dual range: measures from 0 to 999 ppm with a resolution of 1 ppm. from 1000 to 9900 ppm with a resolution of 10 ppm.Field of application: This product can be used in water purifiers and filters, in food quality control (vegetables, fruits) and drinks, in swimming pools, spas, aquariums and hydroponics. Technical characteristics.Name: Water Quality TesterColour: BlueType: Portable Water Quality AnalyzerMeasuring Range: 0-9999ppmError range: 2%Temperature range: 0-80CBattery: 2x1.5v (CR2032 Button Battery) Product Size: 15.5*3.1*2.3(cm) Inventory.1*Water Quality Detector