Our warmest fleece, made to enhance mobility in frigid temperatures and prevent windchill nightmares. Now with a toastier fabric package - variegated fiber R2 on the inside and full-loft R2 on the outside, sandwiching a windproof laminate - our stretchy R4 excels alone or under a shell. Its lack of shoulder seams allows pack-wearing comfort, and the high-placed handwarmer pockets stay clear of a harness. The women's jacket has invisible zippers on the handwarmers and feminine contouring. Made in USA. Regulator SystemRegulator is an integrated system (base, insulation, shell) that works in unison to keep you dryer and more comfortable over a wider range of conditions than a traditional waterproof layering system.