XIANQI High Precision Tester: built-in high precision temperature sensor, providing 0~100C measurement range and 0.5C accuracy. Celsius/ Fahrenheit display selectable. No Battery Needed: built-in small-scale hydro power system to generate current, no battery needed or power leakage risk. It will automatically turn off after no water flow. 360 Rotating LED Temperature Display: clear LED screen enables you to tester the shower temperature in real time. 360 rotatable for better viewing. Ultra-Practical Shower Thermometer: with this thermometer, we can take shower with just right water temperature, especially suitable for the family with babies. Easy Installation: 1/2 inch nut, compatible with most of the shower equipment, easy to install without any tool needed. ColourSilver Power source:Self-contained hydroelectric power generation Unit count:1.0 count Item dimensions L x W x H:8 x 8 x 3 centimetres Package include:1*LED Digital Shower Temperature Display Water Thermometer Tester