- This light down jacket has been designed for backpacking, yet offers a great design making it perfect for everyday use in cold and mild weather. - Warmth: From 23°F and warmer, this puffer jacket will keep you comfortably warm thanks to its 800-fill-power insulation made with Responsible Down Standard certified down. - Light and compact: the MT100 jacket is packable and weighs approximately 10.2 oz in size M. -Water-Resistant, not waterproof: This jacket will keep you dry for a good amount of time under light rain thanks to a water-repellent fabric.