1.It can provide enough power to operate the refrigerator and charge the battery when driving, allowing you to reach your destination with everything ready to go. 2.Lighting available A power supply for the caravan's interior lights is also available in the holder so you can use your car battery to run your caravan's lights while you are hitched up. 3.This will also operate your high beams at the rear of your trailer/caravan. 4.Long-term use Black plastic construction prevents rust and extends its service life.Easy to install and use, it plugs in. 5.Ideal for use with removable tow bars.You can hide the sockets with this product and not show the electricity when you are not using the tow bar.Trailer main function, RV taillight signal synchronous display Utility range commercial vehicle/semi-trailer/trailer