Polarized sunglasses block glare from light reflecting off flat surfaces, making them very popular among people who spend a lot of time outdoors, driving or particularly near water. Light-sensitive people and those who have had cataract surgery can also benefit from wearing polarized sunglasses. STATS UV Protection: 100% Light Transmission: 11% Lens: 1.2mm High Index Plastic Look Thru Color: Grey/Blue WHAT&';S IN THE BOX 1 Pair of Pit Vipers 1 Tie Downs(TM) Retainer Strap 1 Limpcloth(TM) Size Guide: Single Wides FRAME WIDTH 5.43in (Merika) 138mm (Metric) FRAME HEIGHT 2.28in (Merika) 58mm (Metric) NOSE OPENING 1.29in (Merika) 33mm (Metric) Size Guide: Double Wide&';s Frame width: 5.86in (Merika) 149mm (Metric) Frame Height: 2.34in (Merika) 59.5mm (Metric) Nose Opening: 1.41in (Merika) 36mm (Metric)