The new Beta RoS Jacket follows in the footsteps of all Castellis Rain or Shine (RoS) collection by providing superb dry weather performance and wet weather protection. But it follows in another way too. Like the Gabba and Perfetto before it. It is a revolution in cycling jackets.The Beta is a thin wind and splash barrier that provides a surprising amount of warmth while being incredibly lightweight. At 212g in a size large the Beta is lighter than many long sleeve jerseys. In fact, it is so light you will likely not even notice it, but you will still have the protection promised by many jackets.The jacket achieves the triple crown of wind and rain protection, breathability, and low weight by using a combination of Castellis lightest and stretchiest fabrics, Polartec® Neoshell® and Nano Flex Light.Polartec® is used on the front and the upper of the sleeves to provide windproof and waterproof protection where you need it most. Nano Flex Light woven fabric is used on the back allowing