DESC: SuperThin (ST) Glass Lenses. Twenty percent thinner than conventional laminated glass lenses. (1.8 mm versus 2.2 mm) PolarizedPlus2& Technology. A patented polarizing film with a bi-gradient coating and anti-reflective treatment to eliminate glare and block UV rays. Uses three rare earth elements to naturally enhance color the eye perceives. Spring Hinges gently hug the head for lasting fit and comfort. Nickel/Silver Alloy hinges provide strength, easy movement and corrosion resistance. Saltwater effectiveness. Lens treatments and frames are saltwater safe. Three Lens Hues - Offer patented glare and UV protection under different lighting conditions. Maui Jim& warranties their sunglasses for one full year against any defect in materials or workmanship. Please see our "Returns and Exchanges" information page for the Maui Jim& repair and customer service contact information.