The HI 9811-0 and HI 9811-5 are complete, versatile, rainproof portable combined meters designed with utmost precision and simplicity. Both models provide measurements for pH, EC and TDS ranges, which are easily selectable through a membrane keyboard on the front panel. Conductivity measurements are automatically compensated for tem- perature changes with a built-in temperature sensor. The temperature coefficient is fixed at 2%/°C. HI 9811-0 is a pH/EC/TDS meter designed for simplicity of use in taking pH, µS/cm and mg/L measurements. Suited for hydroponics, greenhouses, aquaculture, food and beverage industries.