Despite often being mistaken for feathers, down is really the soft clusters underneath a goose’s feathers that insulate them in cold weather (who would have thought?). The lofted down filaments overlap and create small air pockets that trap warmth or body heat.
Wherever you find a down garment, you’ll usually find a fill number (such as 650-fill down or 800-fill down). Often mistaken for QUANTITY values, the fill rating actually indicates the QUALITY of the down within that jacket, sleeping bag, or what-have-you. Read More …
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Until some marketing genius turned ‘going green’ into the trendiest thing since the Live Strong bracelet and people started considering their massive environmental impact, technical fabrics used for outdoor clothing were strictly synthetic affairs. Chemical- and oil-based polymers comprised the bulk of waterproof outerwear, fleeces, and gear.