Castelli makes the Tutto Nano from the same Nano Flex 3G fabric it uses for its warmers and Sorpasso tights. The high-stretch fabric creates a close-to-body fit that moves with you and does no flap, which in turn helps keep you warm.The fabric has Castelli’s proprietary nanotechnology water-repellent treatments. On dry days you won’t notice it, but when the rain comes you will stay drier than in a normal thermal jersey and be able to get by for longer without having to reach for a jacket.When it comes to breathability, the Tutto Nano strikes a perfect midpoint between thermal jerseys and the water-repellent GORE-TEX® jackets in Castelli’s RoS line-up. The Tutto Nano fabric is a tighter knit than the fabric used in thermal jerseys so it lets less air through keeping you warmer, but it is also more ventilating than GORE-TEX® so you don’t overheat when the temperature does begin to rise.Castelli’s attention to detail extends throughout. There is 360° reflectivity thanks to panels on the shoulders and lower back, a YKK® zipper with a rubberised pull, and an elastic silicone gripper at the waist holds jersey in place.Features:Nano Flex 3G fabric features warm brushed fleece inside with 20% elastane for stretch and Castelli’s Nano Flex water-repellent finish3 rear pocketsReflective fabric inserts at shoulder and central pocketYKK® Vislon® zipperEmbossed logo12° – 18°C / 54° – 64°FWeight: 301g (Small)