HARNESS THE STRENGTH OF A SILVERBACK GORILLA Classic shape with new levels of style and performance. We designed these shades to look good and fit comfortably on your face whether you're hopping over flames or flippin' tires. Features No Slip: special grip coating to help eliminate slippage when sweating. No Bounce: the frame is snug and light-weight with a comfortable fit to prevent bouncing while running. All Polarised: glare-reducing polarised lenses and UV400 protection that blocks 100% of those harmful UVA and UVB rays. All Fun.