The Bantamweight is insulated with exceptionally high quality down: its fill power rating is a whopping 900+. This, together with superlight fabrics and a short zipper help bring the bag's weight to a level you usually see with summer bags. As is common nowadays, the insulation is impregnated with Down Defender, to reduce the bag's reaction to damp conditions. It also reduces the down's tendency to clump together. - Regular size: for max. 183 hikers, shoulder girth 153 cm, hip girth 137 cm, foot box girth 115 cm - Narrow Slim mummy shape - 500 grams of fp900+ quality RDS certified goose down - Surface and liner fabric are 7 denier mini ripstop Nylon - Shaped baffles help keep the down in place.