DC to DC Charger Kit — Charge While You Drive

A tow vehicle's 7-pin will trickle a few amps into the house battery and no more, and on a modern smart alternator it may put in nothing at all. A DC-DC charger takes the alternator's output and charges the house bank at a real rate on the right profile — 50A here, which is roughly 600W of charging for every hour you drive. The shunt tells you whether it is working.

The parts in the one-click kit lead this list, followed by the other sizes and brands that do the same job, so you can swap a part before you buy. The whole kit, priced and loaded in one click, is on the RV power bundles page.

See what driving adds. The free RV Solar & Battery Calculator counts your daily drive hours against solar and battery size, so you can see how much the DC-DC charger offsets.