A damping felt was installed at the factory between the headliner and the roof to improve acoustics. The same material can also be used as padding material in places where the headliner is mounted directly on the bodywork, with which the sheet metal part is padded.
When upholstering the seats, you will find that this material has also been used between the seat padding (horsehair) and the springs. This protects the seat padding and prevents the development of noises that can be caused by the springs.
If the damping felt is to be glued, e.g. against the roof or between the side wall coverings, it is best to use spray glue.
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