After doing research for belay parka in mid-winter Canadian Rocky weather, I desided to take this. But not many stores curry this, so I couldn't try before ordering, and wondering between XS and S. I'm using men's S, women's S & M with Patagonia, depends on what kind of fit I wanna get for the activity. Since I was going to use this especialy for cold belay time on ice, I decided to go S. Sure it makes me look like huge frosty, but I can fit it over hurness full of gears and even ice ax, and covers my bum compretely while inner pockets hold wet groves and even camera to keep it warm. Impressive. So warm, so comfy, only problem is that it exaggerates how it's cold where it's not covered by DAS.