The frit is a black band running along the edges of a windshield. It is essentially a baked-in ceramic paint and has several functions. Firstly, it protects the urethane sealant that holds the glass in place from ultraviolet rays. Secondly, it conceals the dirt that gathers along the edges of the glass. As for the dots, they provide a visually pleasing transition from the black frit band to the transparent glass. They also create a more even temperature distribution during the manufacturing of windshields.