One button to switch function.Whole machine waterproof.Battary can be replaced easily. Portable design for easy carrying and storage. Quick and accurate test. and clear screen to view the value. Real-time display the remaining battery power. 7 in 1 is the latest multifunctional water quality tester with 7 functions product, which can be used multiple times. It can measure PH/TDS/EC/ORP/specific gravity/temperature of sea water. The measurement range is and wide, and can measure water salinity and sea salt. It is suitable for digital water quality monitor , swimming pool, drinking water and aquarium. 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: 0.01-14.00H 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: 0-60.0C (32.0-140F); 100% relative humidity TDS factor: 0.5 Temperature range: 0.1-60.0C 32.0-140 Temperature accuracy: 0.5 Temperature Resolution: 0.1C/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.