The 20A dual BlackBull charge regulator has the peculiarity of being able to charge through the solar panels that it has simultaneously connected to two batteries (or two banks of batteries even of different capacities) independent at the same time.
Very suitable for motorhomes, since it will charge the vehicle's starter battery on the one hand and, on the other, it will charge the caravan's service battery for household consumption. This DUAL regulator has its corresponding instructions in Spanish. Easy to configure.