Optimal insulation for running on cold days. The Zeroweight Insulator Jacket, made with 91 percent recycled materials, features Thermo insulation from Freudenberg, which is produced from recycled PET bottles and provides an exceptionally high level of warmth. The windproof 4-way stretch fabric moves with you, while the lightly insulated hood and reflective details enhance your comfort and visibility. The zippered side pockets offer space for all your essentials on the go. You'll see: with this jacket, running in sub-zero temperatures is truly enjoyable. Enjoy maximum warmth and breathability on cold days. Run lighter and faster, dry quickly, and experience incredible lightness: performance running apparel that leaves all others behind.