Sustainable design that doesn't sacrifice performance in cold weather around 20°F. The PFC-free, mummy-style Women's Trestles Elite Eco 20 Long Sleeping Bag fill is made from 96% recycled material, and has the lightweight, easy compressibility of the original. The female-specific cut adds extra insulation for more warmth where you need it. HL-ElixR™ Eco Micro synthetic insulation uses a unique blend of three fibers for maximum warmth, soft handfeel, and high loft. Wave and blanket construction plus a roomy footbox provide optimal warmth and comfort. A fold-down secondary zipper offers ventilation and easy access.