The Swix RaceX top is part of Swix’s popular baselayer range. The RaceX baselayer has won countless tests over the years and is preferred due to its light and elastic fabric. The open structure of the fabric holds a thin layer of insulating air against the skin, while offering outstanding breathability and ventilation properties. It is a fast-drying material and its structure is designed to absorb moisture from the skin. These are some of the reasons why your baselayer is so comfortable and temperature-regulating during high activity. Swix Signature line. Made for athletes, worn by everyone.