Internal Transponder
  1. Clean and dry inside your windshield around the rearview mirror.
  2. Without removing the self-adhesive strips from the tag, remove the tape backing from the self-adhesive strips.
  3. With the E-ZPass tag label right side up facing you, adhere the tag inside your car to the upper center portion of your windshield. Place it behind the rearview mirror at least one inch to the right of the center support of the mirror and at least one inch below the top edge of the roofline.
External Transponder
  1. Remove the screws holding up the top of the license plate to the vehicle.
  2. Using those screws, mount the transponder on the license plate aligning the two holes on the bottom of the transponder. The transponder must be mounted so the tag label "This Side Up" can be read.
The transponder should be mounted on top of the license plate. You may use the top holes on the transponder only if it is not possible to mount it with the bottom holes.

Note: Trucks, buses and some passenger vehicles may need exterior-mounted tags.