It was made for trail running, but even Steve House uses it for ice climbing on Nanga Parbat.There's nothing you can't use this thing for. With a lot of force, it stubbornly stuffs into its zippered chest pocket that can barely fit a naked iPhone 5. The shell material is light and doesn't feel sticky and clammy if you actively unzip it once awhile for quick venting. The cuffs on the sleeves are a bit odd. The elasticity is only on half of the cuff, (to save weight?), but works just as well so I'm not complaining. The hood had a cinch which is good for the smaller headed folk; I have a scary big noggin' so it's not much use to me. Theres not much else to the jacket With the R1, I can run comfortably in the 30s. I haven't tested it for backpacking, but I can't imagine why you wouldn't since it weighs so little. To the ultralight crowd, you guys probably have this already and can attest to its versatility. Great jacket, highly recommended.