Features: 1DEAL WITH VARIOUS OCCASION: TDS test pen is suitable for domestic water, aquaculture, swimming pool and other water quality detection 2HIGH SENSITIVITY PROBE: Water quality instrument has alloy probe and high sensitivity glass electrode, realize high accuracy water quality measurement, support automatic temperature compensation, reduce error 3SCOPE OF USE: Water quality tester can be used for domestic water, swimming pool, aquaculture, environmental water quality, agricultural water, aquarium water quality, greenhouse flowers, bottled water, community water station 4WITH BACKLIGHT: The water quality tester automatically turns on the backlight display when turned on, allowing you to see the value even in dim conditions 5CELSIUS FAHRENHEIT DEGREES SWITCH: TDS meter with temperature unit switch function, very flexible and practical Package included: 1 x Tester 1 x Storage Bag&nbsp 1 x User Manual