One time I went through the car wash and the thing ripped off my headlight covers!
I started driving away and I heard this awful scraping sound I was like wtf??? So I stopped the car and looked under neath and I had been dragging one of my headlight covers.. thing was scratched to sh*t! lol. They're only $40 but I'll never go through a car wash again.
Those things are powerful, and they scratch up your paint too.