magnetic lens changing system for all weather conditions . the sinner sin valley is a high performance goggle with magnetic lens changing system. this allows you to change lenses in less than 5 seconds to adapt them to the weather conditions. the ingenious ventilation system and the anti-fog coating prevent fogging of the lens. the soft, 3-layer hypoallergenic foam on the inside provides an excellent fit and maximum comfort.double orange oil lensthis lens has a mirror coating and reflects bright sunrays. perfect for sunny and changeable days.transmittance of visible light: 18 - 43 %bonus lensthis bonus lens is perfect for cloudy days with poor visibility.filter category: s4