If you want one jacket that you use in bounds and out, the men's Burton [ak] Hover GORE-TEX C-Knit 3L Stretch Jacket is one of the lightest, most packable shells in the [ak] line.
Crafted from cotton flannel fabric, this plaid button-up shirt offers a regular fit with a traditional collar neck, two chest pockets, a scalloped hem, and Dayshift Collection trims throughout.