My standard top for XC or BC skiing in the PNW. Zipped up, the high, super comfy collar provides welcomed warmth. When working harder or out of the wind, the collar disappears when the front zip is undone. Thoughtful use of different fabrics includes thinner, perforated material on the back. Use of merino keeps the stink away even after days and has never itched even though I'm somewhat sensitive to wool. The chest pocket is handy for car keys or a gel and additionally sets this top apart from a normal long sleeve zip tee thermal. Contrary to the other reviewer, I find the sizing as expected. The fit around the waist is a bit athletic, but as long as your belly is smaller than your chest...
The one improvement, at least for my usage, would be to make the cuff compliant enough to let the sleeve be pushed up to the elbow for greater cooling.
versatile base or single layer 
