Castelli's Aria Shell Jacket is very different from your old wind shell that buffeted with the wind and either didn't protect you or didn't breathe well enough to keep you dry and comfortable. This jacket is an impossibly light layer that keeps the wind off the front of your body while allowing the necessary ample breathability through the mesh side panels. But what you'll really appreciate is how Castelli has chose to 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 90's or early 2000's.

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. This is truly an extremely light and packable wind shell that fits close to, and moves with the body, allowing you to extend the temperature range of your favorite Castelli pieces.