Our synthetic down is constructed with short-staple insulation that features short fine denier filaments to reduce heat loss. This makes for great compressibility, unlike their continuous filament counterparts making ours much like real down. With a tested and designed to operate -20 F, meant for some serious cold.
Our polyester insulation dries very quickly and maintains to hold warmth even when it's wet, something a traditional down cannot do. This makes this puffer much more functional during a variety of weather systems without a hardshell.
The addition to underarm vents in in a down jacket is the most functional feature for heat extraction. If one was to accumulate perspiration in subzero temperatures that can be a deadly situation.