It depends. You need a FasTrak Flex toll tag if you are a carpool, vanpool, motorcycle or other carpool-qualifying vehicle that will use the Bay Area Express Lanes. Otherwise, your standard FasTrak toll tag will work in all express lanes and other FasTrak facilities.
If you drive an eligible clean air vehicle (CAV) in the Bay Area Express Lanes as a single occupant, you must have a FasTrak CAV toll tag to receive the 50% discount. Solo drivers in eligible CAVs using a FasTrak Flex or standard FasTrak toll tag in these lanes will be charged the full toll.
Topic: Toll Tags