Day and night sport glasses: Photochromic lenses adjust based on sunlight and UV exposure, darkening from light yellow to provide optimal clarity in varying light conditions. Unlike traditional sunglasses that remain permanently dark, these lenses automatically adapt when moving indoors or into low-light environments, ensuring comfortable and clear vision for improved safety during activities such as driving. UV400 polarized lenses: Provide 100% protection against harmful UVA and UVB rays. The TAC polarized lenses reduce glare from reflective surfaces like roads, water, snow, and LED lights from vehicles. Enhances visibility in low-light conditions, improves contrast on dark areas alongside roads at night, and delivers clearer vision during rain or fog, resulting in a wider, sharper, and safer field of view. Sturdy and durable flip-up design: Features a precision-engineered spring hinge for smooth, reliable flipping motion that resists breakage and sticking. Each arm includes a rubber sleeve to prevent slippage and protect your primary eyewear from scratches. Easily flip up when not needed, eliminating the need to remove the glasses, with no frame arms obstructing peripheral vision. Ultra-lightweight construction: Weighs only 8 grams, offering a nearly weightless feel for all-day comfort. Designed to be worn over prescription glasses without the need for multiple pairs. Perfect fit and satisfaction: If you experience any quality issues or are not satisfied with the product upon receipt, please contact the seller for return and exchange options.