Features It is a multi-functional water quality pen that can measure ph, TDS, ec, salinity and temperature. With high performance, pen design, fast numerical stability and accurate calculation results. Lightweight and portable design, convenient for indoor and outdoor use. Made of quality material, highly efficient and accurate. Large and clear display screen, easy to read the displayed value. Material: Plastic Color: As shown in the picture Battery: 3 x LR44 button battery (Not included) Conductivity Test Range: 0 to10000uS/cm 10.01-19.99ms 20.1-400mS/cm Resolution: 1uS/cm; 0.1mS/cm Accuracy: ±2% of reading TDS Test Range: 0 to 1000ppm 1000ppm to 10000ppm 10.1 to 200.0ppt Resolution: 1ppm; 0.1ppt Accuracy: ±2% of reading Salinity Measurement Range: 0.00 to 25.00% Resolution: 0.01% Accuracy: 0.01-5.00% (±0.1%) 5.10-25.00% (±1%) pH Test Range: 0.01-14.00pH Resolution: 0.01pH Accuracy: ±0.05pH Temperature Compensation: Automatic temperature compensation (ATC) Working Environment: 0 to 60.0 ° C (32.0-140 ° F); RH 100% TDS Factor: 0. 4to 1.0 Temperature Range: 0.1-60.0 °C/ 32.0-140 °F Temperature Accuracy: ±0.5 °C Temperature Resolution: 0.1 °C / °F Auto Power Off: 5 minutes Display Screen Size: Approx.33x24mm / 1.3x0.9in Size: Approx.183x37x37mm / 7.2x1.5x1.5in) Weight: Approx.90g/3.2oz Display: No backlight support Waterproof Rating: IP67 Power Consumption: 2.9mA, power consumption for shutdown is 0 Accuracy within 150ppt is relatively accurate, and deviations above 160ppt are large Package List: 1 x PH Meter1 x Instruction Manual Note: 1. Please allow 1‑2cm error due to manual measurement. Thanks for your understanding.2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard.3. Be sure to clean the electrodes after each use.4. Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.5.Product needs to be calibrated before use (calibration powder is not included). Package List 1 x PH Meter 1 x Instruction Manual