Tifosi SlipProtect your eyes in style and chase down a new personal best. The Tifosi Slip eyewear features shatterproof, polycarbonate lenses that offer 100% protection from harmful UVA/UVB rays, bugs, rocks, or whatever else comes your way. The frames of these running glasses are made of Grilamid TR-90, a strong, UV damage resisting nylon. Lens installation/removal is fast and easy. Rubber ear and nose pieces provide a no-slip fit. For your comfort, ear pieces are adjustable for a customizable fit. Certain Tifosi Slip products feature Fototec lenses that rapidly tint as needed, adjusting to changing light conditions and providing exceptionally clear vision and protection. One size fits most.