Waterproof tester for pH, conductivity, salinity and TDS, temperature display, pH: 0.00 – 14.00, resolution 0.01 pH, auto buffer recognition, up to 5 calibration points; conductivity: 3 ranges 0 – 199.9 µS/cm, 200 – 1999 µS/cm and 2.00 – 20.00 mS/cm, resolution 0.1µS/cm, 1 µS/cm and 0.01 mS/cm, 3 calibration points; TDS and salinity: 3 ranges 0 – 99.9 ppm, 100 – 999 ppm and 1.00 – 10.00 ppt, resolution 0.1 ppm, 1 ppm and 0.01 ppt, 3 calibration points; automatic temperature compensation (ATC), microprocessor controlled, large display