This kit allows a motorhome or RV dinghy-towing a vehicle to power the signal lights only on the towed vehicle without power feeding back to the RV or feeding to the rest of the towed vehicle's electrical system. It is rated for 3 amps max per diode block and 24V max per diode block. This kit requires a trailer-side 4-way flat connector plug with 20' wires (such as the CURT #57220) or similar, depending the length of the towed vehicle.