Usage Tips:Product multifunctional water quality pen, which can measure ph, tds solubility, ec conductivity, salinity and temperature. It is a waterproof water quality test pen with five functions .It has high performance, pen-shaped design, fast numerical stability and accurate calculation.result . Settings: TDS Measuring range: 0-1000ppm CE measurement range: 0-10000US/cm pH measurement range: 0.01-14.00 pH Salinity measurement range: 0.00-25.00% Seawater salinity measurement range: 10.1-200.0ppt. Accuracy: 0.01-5.00% (0.1%) 5.01-25.00% (1%) < p > Display size: 33*24mm Weight: 183*37*37mm(7.2*1.5*1.5in)/90g(3.2oz) Weight: 170g Display: supports backlight Waterproof level: IP67 Note: The data is all manual measurement, please allow 1 - 3cm error, due to the difference in light and display, there will be a certain color difference, depending the physical object received Delivery Quantity: (according to the main image)