You can get doublers for the the 12v outlet. They're not very elegant but it's easily removed. Dash cam leads are usually miles long.
USB Car Charger Splitter Adapter, 2 Socket Cigarette Lighter Multi Power Outlet 12V/24V 80W DC with LED Voltmeter Switch Dual USB Port for Mobile Phone Tablet GPS Dash Cam Samsung Tomtom : Amazon.co.uk: Electronics & Photo
USB Car Charger Splitter Adapter, 2 Socket Cigarette Lighter Multi Power Outlet 12V/24V 80W DC with LED Voltmeter Switch Dual USB Port for Mobile Phone Tablet GPS Dash Cam Samsung Tomtom : Amazon.co.uk: Electronics & Photo
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