Waterproof class:IP65 Working environment:0-60(32.0-140.0) RH:100percent Backlight:LCD screen backlit display Automatic shutdown:Five minutes Electric cell:3x1.5V(LR44) (Not included) Screen size:28x20mm Display mode:Liquid crystaldigital display Notes:The electrodes needto be cleaned after use CL2: Measuring range:0.01-4.00ppm (Total residual chlorine) Resolution:0.01ppm Accuracy:10percent reading value, 0.01ppm Temperature compensation:0-60(Auto) H2: Measuring range:0-10000ppb (0.001-10.000ppb) Resolution:2ppb (0.002ppb) Accuracy:10ppb (0.01ppb) Temperature compensation:0-60(Auto) TEMP: Measuring range:0-60 Resolution:0.1 Accuracy:0.1 Colour:Yellow Material:Plastic Package Contents: 1 * 3-in-1 Chlorine Meter 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.