White or Blue may be supplied Portable TDS meter is a professional instrument with multi-function, can be used for testing water TDS (the weight of total dissolved solid of water, unit is mg/L or ppm), conductivity (the ability of conduction current expressed in digit, unit is us/cm) and the temperature. The pen-type design and fast numerical stability lead to an accurate result. • Lock Function: Makes It Easy To Read And Record, Press HOLD Button Then Remove From Test Solution. • 4 Display Modes: Press SHIFT Button: TDS - Ppm & °C, EC - Μs/cm & °C, TDS - Ppm & °F, EC - Μs/cm & °F. • 5 Minute Auto shut off feature, so battery won't deplete. • Measurement Range: Conductivity: 0 - 9990 Μs/cm TDS: 0 - 5000 Ppm (parts Per Million) Degrees Celsius: 0.1 - 80.0°C Fahrenheit: 32.0 - 176.0°F Accuracy: ± 2% • Net Weight: 55g Includes: 1 x TDS Meter 1 x User's Manual 1 x Battery Included