Door Trim Water-shields 70-81 Firebird & CamaroWhen first produced GM placed a water shield panel behind your door trims to protect them from years of weather penetration.. which does work to a great extent.. but most have been removed and discarded during repairs and resprays etc. You put the Plastic shields on the door shell to it helps to prevent moisture seepage. Use of a sealant.. maybe a windscreen type sealant would work. These are supplied & made ex USA.. and meant to be on cars from