The H2 tester is designed to have a four-in-one function, which can measure PH, ORP, H2. High temperature and high precision at the same time, the all-round measurement quality of water ensures healthy water quality. Portable PH meter can be carried anywhere to measure water quality, such as tap water, RO system water, aquarium, sea water and swimming pool water. The automatic shutdown function turns off the power after 5 minutes without any operation. A completely transparent liquid crystal (LCD) is used to display the 4-digit value and the corresponding physical quantity unit. The green backlit LCD design ensures that you can read the measurement results in any way. The tester consists of high-quality electronic components that ensure high accuracy and replaceable sensor probes. In order to achieve high precision, it is equipped with a high-quality titanium alloy probe and reliable automatic temperature compensation (ATC), which can ensure that accurate readings are always maintained at various temperatures. Three-point calibration with automatic temperature compensation, immerse the electrode in the PH (6.86 and 4.00 9.18) standard solution, and then press the CAL button to automatically calibrate. Specifications: 1.PH Range: 0.01-14.00pH Resolution: 0.01pH Accuracy: 0.05pH 2.ORP Range: 999mV Resolution: 1mV Accuracy: 2mV 3.H2 Range: 0-2400ppb 0.001-2.400ppm Resolution: 2ppb 2ppm Accuracy: 10ppb 10ppm 4. Temperature Range: 0.1-60.0 C 32.0-140 F Resolution: 1? F Accuracy: 0.5 Note: Product need 3 LR44 battery,which dont included in package. Easy to use and provide fast measurementsA completely transparent liquid crystal (LCD) is used to display the 4-digit value and the corresponding physical quantity unit. The automatic shutdown function turns off the power after 5 minutes without any operation. Portable PH meter can be carried anywhere to measure water quality, such as tap water, RO system water, aquarium, sea water and swimming pool water. High temperature and high precision at the same time, the all-round measurement quality of water ensures healthy water quality. The H2 tester is designed to have a four-in-one function, which can measure PH, ORP, H2.