Specification: Features: Economy model that is great for end-users: Highly efficient and accurate due to its advanced microprocessor technology. Hold function: Saves measurements for convenient reading and recording and battery life is approx. Display: Large and easy-to-read LCD screen. Measurement range: 0-9999 ppm. From 0-9999 ppm, the resolution is in increments of 1ppm. Can detect three types of impurities in water: soluble salt impurities-calciums ions, magnesiums ions, etc.; ionic organics-sodium acetate, sodium sulfate, etc.; heavy metal ions-chromium, zinc, lead, copper, etc. Note: The lower the TDS measurement value, the purer the water quality Specification: Size: 150*16*16mm Measurement accuracy: 0-9999PPM Temperature range: 0-80 degrees Celsius Weight: 28g Package List: 1 x TDS Water Quality Testerbuilt-in button battery