When you are out for the day in the mountains you never know what type of weather you will encounter. Luckily, the ultralight 110g Summit Jacket packs up small enough to go with you on every ride, providing reliable wind and water protection, without sacrificing ventilation. The hood is thin enough to fit easily under your helmet. An easy to operate premium two-way YKK Vislon® zipper can be quickly zipped up from the bottom to vent while climbing, avoiding excessive flap. Best of all, when things clear up you can stuff it back into the included envelope pocket.