The cloth mesh was the base of the dam which is placed approx - 3/8" from the edge of the glass then a bead of Thiakol sealer adhesive was run in the 3/8" margin... the latex foam dam was used to keep the sealer from pushing out into the car cabin, it acts to control the adhesive and by retaining it to the 3/8 margin it also keeps the glass from being pushed too close to the windshield frame, which causes issues with how the trim fits to the frame and the glass surface.
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