High precision and 10S refresh Using Triple-A battery (not included). Built-in accurate thermometer hygrometer sensor, temperature and humidity sensors check the environment approximately every 10 seconds, then automatically refresh the on-screen display to provide the most accurate readings. Temperature range is -4F to 158F, humidity range is 10-99%. Switch the unit between Fahrenheit and Celsius with a single tap Precise and fast refresh: The hygrometer refreshes every 10 seconds to provide you with the latest readings. Temperature range -9~60, accuracy 1; Humidity range 20%~95% RH, accuracy 5% RH. 24-hour high and low records: digital thermometer hygrometer Track status throughout the day with high and low records low to ensure a healthy home. Reliable operation buttons on the back for manual adjustment of F/C switching, to easily meet different people's needs.NOTE: Yes backlight function - 10 seconds lighting time Three Placement WaysThe hygrometer thermometer can be placed on the table through the back bracket or installed on the wall through the hanging hole on the back. In addition, magnets can fix the hygrometer thermometer on the refrigerator. you place it wherever you want like refrigerator, counter, living room, baby room, kitchen, basement, office, greenhouse, guitar room, office, garden and cellar Clear LCD screen: it displays Clearly reads and real-time time and temperature/humidity on the LCD display, allowing you to read big and thick numbers clearly even from a great distance. [Pocket Size] With an overall size of 80mm x 59mm x 22mm, the digital thermometer and hygrometer is slim and portable. Save space and easy to carry.