Function parameter: 1. EC: Range: 0-10000us/cm, 10.01- 19.99mS/cm, 20.1400.0mS/cm (automatic range conversion) Resolution: 1uS/cm; 0.1ms/cm; Accuracy: ±2% 2. TDS: Range: 0-10000ppm, 10.1-20.0ppt (automatic size conversion) Resolution: 1ppm; 0.1 point Accuracy: ±2% 3. Salinity: Range: 0-10000ppm, 10.1-200.0ppt, 0.01%-25.00% Resolution: 1ppm; 0.1ppt; 0.01% Accuracy: ±2% 0.01-5.00% (±0.1%): 5.1-25.0% (±1%) 4. pH value Range: 0.01-14.00рH Resolution: 0.01pH Accuracy: ±0.05 4. ORP: Range: ±999mv Resolution: 1mv Accuracy: ±2mv 5. SG: 1.000-1.222 Product Specifications: Waterproof grade: IP67 Temperature: ATC 0-60° Working environment: 0-60.0°C (32.0-140°F); 100% relative humidity TDS factor: 0.5 Temperature range: 0.1-60.0℃ 32.0-140℉ Temperature accuracy: ±0.5 Temperature Resolution: 0.1°C/°F Automatic shutdown: 5 minutes Display mode: LCD digital display backlight Note: Please clean the electrodes after use Batteries: 3 * 1.5V (LR44) Colour:white+blue Material:ABS Package Contents: 1 x Water Quality Tester Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. One button to switch function.Whole machine waterproof.Battary can be replaced easily. Real-time display the remaining battery power. Portable design for easy carrying and storage. Quick and accurate test.Large and clear screen to view the value. 7 in 1 is the latest multifunctional water quality tester with 7 functions and one product, which can be used multiple times. It can measure PH/TDS/EC/ORP/specific /temperature of sea water. The measurement range is large and wide, and can measure fresh water salinity and sea salt. It is suitable for digital water quality monitor in home, swimming pool, drinking water and aquarium.