Depending on the section of the RV system, a different type of wire should be used. For the section between the solar panels and the charge controller it is recommended to use the cables included with the modules and use MC4 extensions if needed. Alternatively, PV wires can also be used. For the section between the charge controller and the batteries it is recommended to use cable types THHN or THWN-2. Same can be applied to the section between the battery bank and the inverter. To learn more about how to wire your off-grid solar system you can visit our article