Some kind of evaluation going on here before going on a morning hike along the Kettle. That's a yellow jacket made of Momentum 90 fabric and 3M Thinsulate 120g/m2. It kept me toasty at freezing temperatures (Don't you just love those evaluations in Backpacker Magazine that read just like this over and over?) Anyway Thinsulate is great. I like it because the gear made with it weighs about 1/2 of fleece (my best guess).