Foam insert is a necessity when using goggle strap for an insured comfortable fit, and can also be used alone. Foam insert can be removed for cleaning and is lined on the interior side with an Anti-Fog treatment coating. The fleece helps keep any dust and wind away from the eyes while also keeping moisture at bay. See instructional video on how to use with your Liquids. Foam is sold separately and does not come standard with the purchase of any frame. This item can be used for motorcycle riding, bicycle, snow skiing, snow boarding, boating, and other outdoor activities that require eye protection.