The Castelli Perfetto RoS Light short sleeve is a durable cycling jersey that withstands the elements that keep many off the bike: wind, cool weather and light rain. The Gore-Tex Infinium 203 Stretch with improved DWR coating is lightweight and does an excellent job of blocking wind and keeping air moisture out. The stretch woven rear panel with Nano Flex water repellent nish has even better water repellency: rain drops just roll off the jersey. It also has lower air permeability which means that while the jersey is more windproof it also has superb breathability. No racer wearing the Perfetto will be slowed down by a sweaty back. The Gabba-style dropped tail protects from road spray and keeps the area between shorts and jersey sealed. If you need a little cooling off, the YKK Vislon zipper opens easily. The two pockets are made larger, so they are easier to access when wearing winter gloves. Included with the pockets is an inner sleeve to securely hold a bike pump. A large, black reective panel across the entire lower back panel provides extra visibility on early morning, overcast or rainy training rides.