NASCAR Racing: car windshied, cheets, pit road

Question
how does a driver clean debris on his windshield while racing?  

Answer
They cant control it while they are on the track, but if they come down pit road there are 2 things the crews can do. One is simply clean it with a squeegee, the other is to take off one of the tear-offs. Tear-offs are clear cheets that go over the windshield in layers, if one gets too dirty, they can rip one off and it leaves a brand new one until the next time the driver requests a change.