Yes. Keep your switchable FasTrak transponder(s) to be eligible for carpool discounts on designated express lanes throughout California. You can have, both, your sticker transponder and switchable transponder mounted to your windshield at the same time.
On The Toll Roads, it doesn’t matter which transponder is read for toll collection because discounted tolls are not offered and every vehicle must pay a toll.
Some tolled bridges, lanes and roads in California offer discounted rates or free rides to carpooling and/or high occupancy vehicles. When driving those facilities with two transponders, the appropriate toll will be collected based on the settings on the switchable transponder if a discount is applicable. For more information on carpooling with FasTrak, visit: TheTollRoads.com/Accounts/FasTrak/California.