Features:Measuring range: 0-4000ppb /0-4.000ppm, resolution 1ppb/0.001ppm. Precision hydrogen meter with high-sensitivity probe. With backlight, data hold function. Easy to operate, carry. Easy electrode replacement. The ATC symbol indicates that the device is in automatic temperature compensation mode. IP67 is an international waterproof and dustproof certification. Protection against dust intrusion, short-term immersion. Ideal for water testing, swimming pools, aquariums, spas, hydroponics, laboratory and drinking water, etc. Package Included:1x Hydrogen Meter Specifications:Material: ABS Size: 183x3 7mm/7.2x1.46in Button Battery: IncludedNote:Please allow 1-3cm error due to manual measurement. Pls make sure you don't mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item.