Mammut's Taiss Light ML Jacket works for most of our mountain pursuits—from mountaineering and ski touring to climbing and hiking. The mid-weight fleece warms us up in cool-to-cold weather, and it slides under our shell easily, thanks to its athletic cut, smooth nylon finish, and thumb loops that hold our sleeves in place when we're layering. The 4-way stretch and underarm gussets give us great freedom of movement when we're climbing or skiing while the zippered chest pocket is strategically placed above our harness or hipbelt.