This is water test pen made of plastic material. It has reasonable design and practical functions. You can use it to test the water and identify whether your drinking water is safe. Fine workmanship, small and compact size, easy to hold and simple to use, will bring you a better experience. Features - Color: Mainly white, green. - Material: ABS, electronic component. - Size: 15.20X3.20X1.60cm/5.97X1.26X0.63inch. - Calibration method: 3-point automatic calibration. - Battery: 2X 1.5V (LR44 ) - PH Range: -2.00-16.00 PH. - Temperature range: 0-80ºC/32.0-176°F. - Reset function: Press and hold the power button for 3 seconds in the power-on state, then release your hand, when the screen appears: "----" reset successfully. - Automatic temperature compensation function: 0-80ºC. - Power-off data storage function: After the battery is pulled out, the data will be automatically saved, and the storage time will be one month. - Test paper function: The color of the backlight will change with the PH value, just like litmus paper. - Made of high-grade plastic material, and , not easily damaged. - Efficient and useful, can help you quickly test water PH, can be used for drinking water, also for testing temperature. - The design is reasonable, compact and portable, and can be carried with you to test the water anytime and anywhere. - You can use it to test the purity of drinking water to ensure your drinking water is safe, with digital LCD display, precise and useful. - It has a wide range of uses and is suitable for all kinds of hydroponics, swimming pools and spas, aquariums, etc. Package list: 1 Tester Pen 1 x Manual 3 Bags x PH Powders