The lightest warmest insulation. Period. Our next generation Downlight has deep roots. its ancestor was a favorite of Jim Whittakerâs when he became the first American to summit Everest in 1963. Zippered handwarmer pockets. Contrast First Ascent logo on right chest. Eddie Bauer. Expedition logo on back collar.. 100% ripstop nylon. World's Best Down..: 800 fill power premium northern European goose down. Ultra light ultra warm ultra compressible.. 1.18 ounce 20 denier ripstop nylon with StormRepel. durable water repellent finish. Slim active fit thatâs cut closer to the body with no bunching or binding. Weighs less than one pound but remarkably thermally efficient: more warmth less bulk. Easy running zippers. Elastic binding at armholes and hem to seal out nasty weather and trap heat. Packs into its own exterior pocket