The Trestles 30deg Sleeping Bag by Marmot is a synthetically insulated sleeping bag that will keep you warm in cold, damp environments and is versatile for almost any season. Made with SpiraFil insulation, which is a unique blend of 3 denier conjugated spiral hollow fibers for loft and 1 denier polyester fibers for warmth, softness and compressability. Designed to keep you warm even when dampened with rain or snow. Wave construction gives you the advantages of a Nautilus hood that wraps around your head reducing heat loss, and a zipper guard keeps the draft tube fabric from getting caught in the zipper, resulting in a midnight battle with your sleeping bag. A versatile, synthetic bag that keeps you wrapped in warmth throughout your night outdoors.