Cover: Ylang-ylang is a richly fragrant flower used in aromatherapy to lower blood pressure and induce relaxation. The Ylang Ylang pillows lightly fragranced cover invites relaxing sleep with its exotic, calming scent. Made with 48% viscose (plant fiber) and 52% polyester.Fill: Natura Smart Wool™ fill creates an insulating layer that helps to regulate temperature next to the skin for a healthy, comfortable nights sleep. Natura Smart Wool™ also wicks away excess moisture, creating a fresh, dry sleep environment that repels common allergens and bacteria that thrive in moist environments.