Waterproof class: IP65 Working environment: 0-60C (32.0-140.0F) RH: 100% Backlight: LCD screen backlit display Automatic shutdown: Five minutes Electric cell: 3*1.5V (LR44) (Not included) Screen size: 28x20mm Display mode: Liquid crystal digital display Notes: The electrodes need to be cleaned after use pH Measuring range: 0~14.00pH Resolution: 0.01 pH Accuracy: 0.01pH Temperature compensation: 0~60 (Auto) ORP Measuring range: 1999mV Resolution: 1mV Accuracy: 2mV CL2 Measuring range: 0.01~4.00ppm (Total residual chlorine) Resolution: 0.01ppm Accuracy: 10% 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: Red Material: Plastic Package Contents: 1 x Chlorine Testing Pen 5-in-1 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.