I believe you filled them with ice and they scooped air to push through as you drive. Dad used to have one and talked about having to stop for ice to fill it.
Instead of steel wooling your stainless steel item, try using rubbing compound. It is finer grit so you should have a shinier finish, but steel wool my cause it to rust. It's a little known fact, but stainless can rust after contact with normal steel.
