Windproof to keep the cold off? Yep. Waterproof fabric? Yep. Super aerodynamic for time trials? Got that one too. So its good for everything but were tired of the you could wear that to the disco jokes. It wasnt that funny the first time we heard it. Silicone-coated Lycra® is stretchy & water proof. Keeps out the wind cold & rain. Highly aerodynamic so its great for time trials. Heavy-duty YKK® zipper. Silicone elastic at cuff. Reflex for night safety. Only 99g (pair)