Underneath the turning mechanism, a soft plastic padding is mounted at the front, onto which the headliner is then stretched.
On many Volkswagen Beetles, this seal is either missing or cracked, so the headliner cannot be tightened against the windshield.
If you want the sunroof inside to look like your Volkswagen left the factory hall back in the day, don't skimp on this padding strip, for a neat final finish, it must be present.
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