Car Solar-powered Clock With Luminous Light Thermometer Humidity Meter 1. The solar-powered model stays lit at night in low light and when vibrated. 2. It comes with double-sided tape, please clean the adhesive area before applying. Position the solar panel toward the light for continuous charging. 3. Push the slider on the back of the product upward to turn on the power. Slide the switch again to change the backlight color. 4. Plug the type-C port on the side of the product into the device to charge and keep the backlight on. 5. Time setting: - Press the UPDOWN button to switch between Celsius and Fahrenheit. - Press the SET button for 3 seconds to enter time setting mode, press the SET button again to enter the setting sequence: hour minute year month date confirm. - In setting mode, press the UP or DOWN button to adjust the digits up or down. - Press the SET button to switch between 1224 hour mode. - Press O to turn on the key light for 5 seconds. 6. The backlight automatically turns on in dark environments or when the car is moving (solar-powered models only). It automatically turns off during daytime or in bright light. 7. The product comes with a backup CR2032 battery (for when the product isnt charging, but you can choose not to use it). 8. Dimensions: 8 x 3 x 3.5 cm