As we travel around the country, we occasionally encounter toll roads. But different parts of the country have different systems:

Our diesel fuel discount program also has a solution to that problem, called Freedom Pass. It is a set of transponders that support toll systems around much of the country:

The transponders come as a package with self-adhesive that can be mounted to the windshield:

We have it mounted in the top-center of the windshield, behind the TV (shown here with our Magne-Shade on):

It works well. The toll charges go on the same account as our fuel purchases. Very convenient.