Kristi King, wtop.com

WASHINGTON – E-ZPass might not be so easy for some vehicles because of their windshields.

E-ZPass helps drivers avoid delays going through toll booths en route to Maryland beaches. It’s the preferred payment system for the InterCounty Connector. And you’ll be able to use it by year’s end when High Occupancy Lanes open on the Virginia Beltway.

But E-Zpass transponder signals can be blocked by some car windshields that have heating elements or heat reflecting glass. E-ZPass suppliers recommend drivers in those situations should purchase a License-plate transponder.

Consumer Reports says there is no comprehensive list of vehicles with problem windshields. A spokeswoman for the Maryland Transportation Authority (MDTA) tells WTOP that MDTA workers processing E-ZPass applications are aware of many that do. They flag problem windshield vehicles during the application process and recommend the exterior units.

License-plate transponders attach to front license plates utilizing the plate’s top two screws. Because the attachment sticks out farther than some drivers are accustomed to, MDTA says they can be easily damaged.

The exterior units aren’t recommended for vehicle’s that don’t actually need them.

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