Lighter than air and super packable, the Headwind Jacket packs a major punch for something that folds down to the size of a tennis ball. The wind-resistant shell keeps gusts and chills out, while still letting your skin breathe. And unlike most windbreakers, it isn't crinkly or stuffy-instead it feels like a barely-there second skin. Topped off with a DWR-finish, this jacket easily fits in your daypack, carry-on, or fanny pack (yes, it's that packable) so you'll always have that just-in-case layer when you need it.