Features: Adopts premium ABS material,eco-friendly, corrosion resistant and durable. Hold function: Saves measurements for convenient reading and recording. Large LCD screen is waterproof, clearly displays the measuring data, easy to read. Auto temperature compensation function, covert to a DTS value at water temperature of 25 °C. When not in use for about 10 minutes, it will automatically power off, which saves battery energy. Applied in water laboratory, aquaculture, swimming pool, aquarium, water quality testing and monitoring. How to use: 1. Remove the pen cap and turn on the ON switch. 2. The pen shall be put into the test solution, and the height of the solution shall not exceed 2 cm; 3. Dry the pen point after the application is finished. Precautions: Avoid soaking the TDS pen in the water, avoid direct light and high temperature, and avoid the impact of the weight and fall Specification: Condition: 100% Brand New Material: ABS Color: White Range: 0-9990ppm Resolution: 1ppm(0-9990ppm ), 10ppm(1000-9990ppm ) Test Accuracy: ±2% Full Scale Working Temperature: 0°C-50°C Battery Type: 2. 1.5V Button Cell Batteries(not included) Size: approx. 14.3*2.4*1.4cm/5.63*0.94*0.55in Weight: approx. 50g/1.76oz Package List: 1 * Water Quality Tester(Battery Not Included) Note: 1. Please allow 1-3cm error due to manual measurement, thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos displayed in photos may be showing slightly different from the real object, please take the real one as standard.