Automatic Calibration - This digital pH meter is factory calibrated. Get fast and accurate results with this digital pH tester. Digital pH testers feature automatic temperature compensation that adjusts water temperature and water quality to get a pH reading almost instantly. High Accuracy - Water pH meters have sensitive electrode sensors that can read accurate pH values. The accompanying detailed manual will show you how to get the best accurate and stable readings so that your swimming pool, general hydroponics and even drinking water have the perfect pH balance. Automatic Temperature Compensation - The automatic digital pH meter kit features automatic temperature compensation that adapts to water temperature and water quality, maintaining pH almost instantly.