From proprietary interchangeable lens system to custom-fitting, no-slip Cushinol temple boots, these sunglasses are built for serious outdoor enthusiasts. They provide sharp, crisp, glare-free vision with increased contrast and depth perception. N3 lenses are polarized, offer 100% UV protection, have an incredibly effective anti-scratch coating and exceed ANSI Z80.3 performance standards against high-velocity impact. Rhyno-Tuff air frames are constructed to endure extreme highs and lows in temperature. Self-adjusting nose pads and ear stems create a nonslip grip. All styles weigh less than 1 oz, have vented frames for a no-fog view and an exclusive lifetime warranty. Includes one set of polarized lenses and one set of SportFlex lenses for cloudy, overcast weather.