Size:California King Duvet Cover slips over your existing duvet insert/comforter, creating new luxury look of your bed. This is a beautiful duvet cover set that will brighten your bedroom. It is made of 300 thread count 100% cotton. The cover has a hidden zipper closure and ties at the 4 interior corners to secure the down duvet insert (not included). The set is smooth, soft, beautiful and durable. Care instruction: Machine wash cold, separately with gentle cycle. Do not soak and bleach. Tumble dry with gentle cycle and no heat. Remove promptly. Warm iron if needed.