"DiSt 3: Water conditioning (softener, demineralisation, aquariums, pollution control),DiSt 4: Agriculture, horticulture, hydroponics, cooling towers, boiling and steam heating plants, water purification,Pure H2O: Pure water, distilled and de-ionised water, steam cleaning, PCB washing, battery checkingHigh accuracy, fast response, easy to read display and long battery life. Single point calibration and auto temperature compensation for reliable readings. Operating temperature range: 0 to 50°C (stock nos. 218-992 and 219-002), 10 to 40°C (stock no. 219-428)Maximum Conductivity = 1999µS\/cmBest Accuracy = ±2 %Resolution = 1 μS\/cmBattery Type = Button Cell (1.5 V) x 4Battery Life = 200 hPower Source = BatteryDimensions = 175 x 41 x 23mmWeight = 95gHeight = 23mmLength = 175mm"