Yes. Each vehicle travelling on the Express Lanes is required to have a properly mounted transponder. If you would like an additional transponder, you may request one by logging into your account. If you have an occasional use for a transponder in an additional vehicle, it is highly recommended that you add the plate to your account and obtain an additional set of adhesive strips so you can mount the FasTrak® Flex® switchable transponder in the additional vehicle prior to the time of travel.