The Paddock Style Bumper Air Ducting is made to improve airflow to the engine bay. It goes right behind where a front license plate usually is and helps bring cool air to the radiator. It’s made for circuit use, where license place can be removed without any problem. Outer dimensions; top 20 x bottom 19 x height 6 cm Inner dimensions; top 19 x bottom 18 x height 3.5 cm Paddock Style Bumper Duct should be ordered at REV9 Autosport https://us.rev9autosport.com/paddock-style-bumper-duct.html as they provide the best service and speed we've seen so far!