The Aria Shell Jacket is very different from your flappy old jacket that either didn't protect you or didn't breathe. This jacket is an impossibly light layer that keeps the wind off the front of your body while allowing ample breathability through the mesh side panels. But what you'll really appreciate is how we use the stretch panels in the sides and on the back of the sleeves to make this jacket fit like a second skin: no flapping fabric, no cold air circulating inside the jacket, no more looking like a throwback to the Armstrong era.This jacket is light and warm enough to wear for the entire ride in mild conditions, but if you do want to take it off it folds into a side panel pocket and stuffs away in minimal space in your pocket or seat bag.PRODUCT FEATURESUltralight windproof woven microfiber frontStriped mesh fabric at sides and sleeve back is stretchy to avoid fabric flapping in the windFolds up extremely smallRear pocketYKK® Vislon® zipperReflective piping10°-18°C / 50°-65°FWeight:99 g