Features: High accuracy: High-precision detection of TDS value, small error, TDS value represents the total soluble solid content in water, the lower the TDS value, the lower the ion content in the water, and the higher the water purity. Wide use: Suitable for testing PH value in drinking water, swimming pools, aquariums,spas or hydroponics Lightweight and portable: Only 17g, which is equivalent to carrying a writing pen, bag, and pocket for storage at will. High sensitivity precision probe: High-sensitivity ensures accurate data, avoids interference by magnet fields when testing water quality, and reduces errors. Easy to use: Just put the TDS test pen into the water to be tested, press the switch, the display will immediately show the TDS value of the water, allowing you to understand the purity of the water more intuitively. Specification: Material: ABS Size: approx.15x1.7x1.08cm/5.90x0.66x0.42in Item model number: TDS-M6 Test range: 0-9999ppm Resolution: 1ppm Battery Specification: 3V (CR1225) Working temperature: 0-60 Color: White Quantity: 1Pc Note: Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Contents: 1xPH Tester Pen (other accessories demo in the picture is not included.)