The Oakley Polarized Square Wire Sunglasses have all the features you could wantfrom spring hinges to polarized lensesin a pair of eyeshades. The polarized polycarbonate lenses block glare from smooth surfaces, such as water and snow, that reflect the suns rays. These lenses are shatterproof and lightweight, as well as contoured to shade your peripheral vision. The sturdy metal alloy frame has a spring-hinge mechanism, so it can withstand being knocked or hit and not get bent. Ear stems feature pads that grip even when you perspire, so your shades dont slide off.