The Traveller Sleeping Bag is great for a summer yurt trip, El Camino pilgrimage, bike tour, or as a lightweight summer backpacking sleeping bag. It's also perfect for those times when you didn't think you had the room for a sleeping bag until the need arose, like impromptu couch surfing, finding yourself stuck at an airport or staying warm on an overnight ferry. 650+fill non-PFAS Ultra-Dry Down keeps you warm on cooler nights and a full length zipper allows for ventilation in warmer temperatures (and lets you couple two Travellers together). Features RDS-certified, 650+ fillpower duck down with a non-PFAS Ultra-Dry Down treatment to stay drier in damp conditions Includes a recycled 20D polyester shell with a non-PFAS DWR finish and a 20D polyester liner for pure comfort The full-length zipper and footbox drawcord can be opened for ventilation, or to zip two Travellers together, or to turn the Traveller into a quilt The shoulder drawstring allows you to cinch the Traveller close when temperatures are cooler than expected Sea to Summit Guarantee is offered for the Lifetime of this product