The Free Element Vest uses ThermoCloud(TM) sheet insulation with strategic core baffles to add real warmth without restricting movement on the trail or the skin track. It packs into its own hand pocket with a carabiner clip loop, so there's no reason to leave it behind on a long day. A recycled nylon ripstop shell and recycled polyester insulation and lining keep the build light while cutting down on new material. What Our Gearhead(R) Experts Are Saying:"I've worn this climbing a steep skin track and never felt weighed down or overheated. The baffles at the core let me move freely while the insulation still holds warmth at the stops."