kelty COSMIC SYNTHETIC 0

The Kelty Cosmic Synthetic 0 is a winter-rated mummy bag insulated with CirroLoft ECO, a synthetic fill made entirely from recycled fibers. EN 13537 testing puts it at -8°C comfort and -16°C limit, placing it in the four-season winter category for trips with sub-zero nights. That warmth comes at a weight cost: at 2180 g total with 1740 g of fill, it's heavy for a synthetic bag, better suited to base camp or car camping than a multi-day thru-hike where every gram matters. The shell is recycled 20D polyester taffeta with a 50D taffeta liner, both DWR-treated, backed by a full draft collar and draft tube along the two-way zipper. The adjustable, contoured hood, internal pocket, and stuff sack round out the feature set. Internal length is 199 cm with a regular fit rated to 183 cm user height. Synthetic fill keeps performance consistent when damp and costs less than down of comparable warmth, but the trade-off is a lower warmth-to-weight ratio — the Cosmic Synthetic 0 suits campers prioritizing reliability and budget over pack weight.