Cigarette Lighter Splitter QC... https://www.amazon.com/dp/B07SL3KLS6?ref=ppx_pop_mob_ap_share
There is no way to tell the 12v battery current voltage in the Clarity. My solution was to but a 12v plug adapter that shows the voltage. Cigarette Lighter Splitter QC... https://www.amazon.com/dp/B07SL3KLS6?ref=ppx_pop_mob_ap_share