Flow fills the racers need for a wide field of view and a rapid change lens system. Each kit includes a sunny day Cat 3 lens and a high contrast low light #1 or #2 lens. Flow has also been optimized for perfect comfort through 3 layers of foam with soft fleece against your face and just the right amount of air flow for hi speed skiing. The goggle also has micro google clips that mate perfectly with FIS helmets and an adjustable 45mm strap with silicone for optimal fit and secure positioning on the helmet. The Flow is OTG (fits over the (RX) glasses), has Italian anti-fog acetate inner lens. Flow is used by several national teams.