Unlike the hard non-adjustable nose pieces of Ray Ban sunglasses, sports sunglasses will not slip down your nose when you sweat or when you move your head when running or cycling.
Really good sports sunglass arms should also Discounted original wayfarer sunglasses be sticky and flexible, and they should not move if you get sweaty. The AMO sunglasses are great examples of this.
Ray Ban sunglasses use glass lens material and basic plastic frames that are not safe for sports.
Really good sports sunglasses should be made of superior materials. As a minimum, the sports sunglasses frames should be made of raybans sunglasses sale uk TR90 which is more resistant and flexible than basic plastic/nylon frames. Ray Ban sunglass frames are made of hard plastic with a low tensile strength that can easy break and may shatter.
If your wearing Ray Ban sunglasses and you fall over, or off your bike, with glass lenses they could shatter and damage your eyes and face. Also some ray ban sunglasses have glass lenses, which for sports are a definite 'no, no'.
For sports sunglasses the lens should be made of 2mm thick polycarbonate which not shatter and ideally should also comply with ANSI 87.1 – an accepted lens safety standard