Marmot Women's Trestles 15° Sleeping Bag

The Marmot Women's Trestles 15° swaps down for SpiraFil synthetic insulation, keeping the bag performing even if it gets damp — a real advantage in humid climates or where drying gear mid-trail isn't practical. Comfort is rated to -8.5°C with a -15.8°C limit under EN ISO 23537, using 793 g of fill inside a 70D polyester shell and embossed polyester liner, both DWR-treated. At 2040 g and a warmth-to-weight ratio of 7.7, this is a heavier bag for its temperature class than the down-filled options in the range — synthetic fill is simply less warmth-efficient per gram, reflected in a fill efficiency of 2.0 and roughly 129 g per degree. The trade-off is durability and low maintenance: synthetic shrugs off compression and moisture better than down over repeated trips. A left-side, full-length two-way zipper, insulated draft collar and draft tube, and a compression stuff sack round out the package. Packing to about 16.2 L, it suits car camping and budget-conscious three-season backpacking up to 170 cm rather than weight-critical thru-hiking.