1. Widely applied to input DC 12V Car, Van, Boat, Marine, ATV, RV etc. 2. The car usb socket is built in with an on / off switch for power control,You can control it any time to save power and extend the life of the product and devices 3. Compatible with all USB-powered devices including phones & tablets 4. Built-in voltmeter provides a fast and easy way to show the car battery status in the screen. 5. LED luminous digit figure for checking the data at night or in darkness. 6. Both the QC 3.0 ports work simultaneously with total output up to 36W.