Sleep comfortably through all the seasons with the Opulay All Natural Adjustable Duvet. Made from 100% natural fiber, the Opulay duvet regulates your body temperature by wicking the moisture. Likewise, the breathable wool fiber keeps you cool in the summer and warm in the winter. It also absorbs up to 30% of its weight in moisture and draws perspiration away from your skin so you can sleep dry. Additionally, wool offers each person a different climate zone so you and your partner can relax optimally. The adjustable duvet comes in two versions to suit all four seasons. The summer version is 200 GSM (Grams per Square Meter) while the spring and autumn version is 400 GSM. The duvets also come with handy buttons so you can easily attach them to create a thick 600 GSM winter duvet.