3-in-1 Water Quality TesterTDS Meter, EC Meter and Thermometer. You can use the mini water quality pen to test water used for drinking, hydroponics or filling your fish tank. Auto-off 0026 Auto-lock Function Turn off meter after 5 minutes of non-use to save battery, the LCD display can record measurements. Super convenientAutomatic temperature compensation function when the meter is in measurement mode. Saving PowerPowered by 1 x 3V CR2032 battery (not included), which can continuously work about 1000 hours. UsageYou can switch between TDS and conductivity by clicking the SHIFT button. Press and hold the SHIFT key twice to toggle between Celsius and Fahrenheit. Powered by 1 pc 3V CR2032 battery (not included), which can work continuously for more than 1000 hours. Product Description 3 in 1 Digital LCD Water Tester Tester of water quality Healthy water Product details Scenes to use It can recognize drinking water, industrial water, industrial water and breeding water. Professional safety barrier, good health and happier life Features: Type: Handheld Water Quality Tester Accuracy: 2% Test Item: TDS, EC, Temperature TDS : 0 ~ 9990PPm CE: 0 ~ 9990 us/cm Temperature measurement range: 0.1 ~ 80.0 Fahrenheit: 32, 0~176.0 Power supply: CR2032 battery (3V) X 1 (not included) Size: approx. 3cm x 15.5cm x 1.4cm / 1.1" x 6.1" x 0.5inch Package weight: about 60g CE value at indicative Drinking pure water: EC = 1 ~ 10 s/cm Drinking water: EC 2000 s/cm Polluted water: EC 2000 s/cm TDS range 0026 amp; Standard for reference only 0~49 Ideal drinking water 50~99 mineral water 100~199 hard water 200~ 399 Reluctantly acceptable water 400~499 bad water 500 polluted water as specified by US EPA Package includes: 1 X Water Quality Tester (without battery) 1 X User Manual Note: Keep the electrode clean, cover the electrode protective sleeve, remove the battery for a long time at idle. Above "Reference Value Range" is just for your reference, depends on different requirements, the reference value may be different for people in different countries or regions. Please read the instruction manual carefully before use.