I've heard the term DC to DC charger but didn't know what it was. Now I do.
so I'm clear, it ups the amperage output from the TV to the batteries for a better charge to run the inverter while traveling. And you have to manually turn it on and off.
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Tony & Donna
2022 Montana HC, 295RL, Solar Flex 400, Onan 3600 LPG, 2K inverter, 200AH Lithium. 2020 GMC Denali 2500 6.6 Duramax, Demco 21K Auto Slide