"Triumph Hill" Mulberry silk comforters comes in 100% cotton casing with 300 thread-count cotton cover for softness and durability. Our Mulberry Silk Comforter is lightweight and hypo-allergenic. 100% pure and natural long strand mulberry silk floss. It is long-lasting, temperature adjusting, breathable, luxurious, very lightweight, flows naturally over your body, is naturally hypoallergenic and requires no chemicals for processing, and is a natural, renewable resource. Using silk can also save you money while also helping the planet, by allowing you to lower you thermostat on cold winter nights.