The Coefficient Hoody from Black Diamond is made from the superb Polartec Power Dry fabric. The qualities of this fabric is what makes this garment extremely versatile; the high loft waffle grid on the inside not only traps warm air but it is also super efficient at picking up & moving moisture away from your body, which in turn helps to cool you down. All this is accentuated by the trim body hugging fit that aids the previous points I have made, but it also means instead of using it just as a midlayer, it will also fair up very well as a stand alone piece on those warmer days. It features an under helmet hood to help keep in more warmth on the cooler alpine days & the stretch cuffs keep bulk down to a minimum when layering. For added comfort around the facial region there is a lovely, soft brushed micro suede collar lining & for storage you have a zippered chest pocket. You dont really need to look any further when it comes to versatile layering pieces. Great for pretty much anything alpine related, backpacking, expeditions, ice climbing, ski mountaineering & touring. Or if you are in between trips it is also good as a thing just to throw on when youre heading into town & its a bit chilly. Under-the-helmet hood Brushed microsuede collar lining Zippered chest pocket Stretch cuffs