Dual level LCD with temperature display. Waterproof and designed to float. On-the-spot measurement with temperature display.The tester allows up to two-point calibration. Press the CAL key and the display shows the standard buffer PH needed for calibration. Immerse the PH electrode into the calibration solution as indicated and press the CAL key. The tester is now automatically calibrated. Measuring range 0~19990ppm Temp -50?~70?, Resolution 10ppm Temp 0.1?, Accuracy ±2?F·S Temp ±1?, Display 4-digital LCD, Environment Humidity:?95?, ATC 0?~50?, Power Supply 4×1.5V(AG13). This instrument and built-in microprocessor chips, good looking, feature-rich, easy to use, with the following notable features: High accuracy 0.001. New designs, large screen displays. User-friendly interface, stability indicating identity. Three standard, two-point or single-point automatic calibration. Automatic temperature compensation, or manual temperature compensation of. Wide range of PH and redox potential measurements