All Season Down Alternative Duvet All season down alternative duvets are made with a certified organic cotton exterior (Global Organic Textile Standard Certified) that effectively manages heat and moisture throughout the night, giving you a cooler, healthier sleep. The fluffy duvet filling is made of down alternative which replicates the feeling of a 100% down comforter. Details * Made with 100% Organic Cotton Shell and Down Alternative Fill, Down Alternative Duvet consists of sterilized and hypoallergenic down alternative microfiber fill with 350 GSM fill weight suitable for summer/spring. The duvet insert is soft, warm, hypoallergenic, and lightweight.