All About Towbars: Towbars allow your car to tag along with you on your RV trip when you need more nimble wheels for around town. Now What?: Tank dumping. Inverters: Many of the electrical items in an RV are designed to work on 12 volts. But many kitchen appliances and consumer electronics need household 120 volt. That's why you need an inverter! On The Road: Ken and Bernice.