Folds up into a tiny pink zippered pouch the size of a Cliff bar!
I looked at a lot of jackets before choosing this one. I love it!! I was looking for: extremely lightweight, fits easily in jersey pocket, wind and water resistant, and a female-friendly cut. This fits the bill perfectly, plus it's got great venting so you don't overheat in it. I wore it yesterday on slushy roads with a slight drizzle and it kept me warm and dry. When the sun came out, I stuffed it into the cute little included pink bag (it clips to the inside of the jacket) and my jersey pocket. I chose black to avoid the mud/grease problem I had with my last jacket and glad I did. I love the feminine detailing on this jacket too. Like all Castelli clothing, it's a snug fit in your normal size, which I prefer. If you want room for some layers underneath, I would size up. It's not a rain proof jacket, more of a thin layer of wind/water protection. Love it!!