FOX Main PERIL Spark Adult MX GoggleThe best value in dirt bike and mountain bike goggles Gram for gram, the Main Skew Goggles are the best value on the market and feature our Variable Lens System (VLS). VLS makes your goggles compatible with standard lenses (stock) and injection molded lenses (sold separately) within the same frame. They are a heavy hitter and light on the wallet with an expansive viewport, triple layer foam, and tear off lens functionality. FEATURES: Best in class