The black band and accompanying black dots at the top, bottom, and/or sides of a windshield is the windshield frit, which serves a couple of different purposes. Made of ceramic that is baked into the edges of the glass, the frit provides a different texture to the inside of the glass to allow the urethane (the glue) to bond to the windshield for installation. The frit that faces the outside of the glass provides a shade or shield against the sun and ultraviolet light, either to protect the urethane during the installation process, or the occupants of the vehicle, depending on the location of the frit and how far into the windshield it extends.

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