The LIP is an inverted airfoil located above the rear edge of the windshield. As air flows between the windshield and the LIP, it follows the underside airfoil of the LIP and is redirected more vertically. This air eddy then diffuses the oncoming air, in effect, to raise the blast of this oncoming airflow. The LIP is made of an impact modified clear or smoked acrylic to make it more impact resistant as well as scratch resistant, this material is DOT approved.