Time and temperature display automatically and recurrently; With sound sleep wake-up function and display brightness automatically reduced by half in the evening from 6:00 to 7:00am, helpful for energy saving; Built-in clock backup power source (coin cell), when external power is off, it will continue to calculate time, but it does not display and alarm; Two power modes, USB or 4 xAAA battery for power supply; When the alarm time to sound the alarm one minute to "Didi tick", In alarm mode, press any button can stop the alarm; With 3 Button: SET / UP /DOWN, easy to operate; Temperature display in convertible unit Celsius / Fahrenheit. When in 12/24 hour clock, 12/24 hours can be converted. The default is 24-hour system. It can be set to always display time (May be set to the time, date, temperature switch display); Voice features: When in the power saving mode, pat palm or make a corresponding sound to wake the display.