What size is a Superking duvet cover? Rebecca Leonard February 13, 2020 10:55 Updated Follow Our Superking duvet covers measure 260cm x 220cm. The internal flap measures 40cm. Shop Superking duvet covers. Related articles What size is a king size duvet cover? What size is a Superking fitted sheet? What size is an emperor duvet cover? What size is a Superking flat sheet? How do ply yarns affect the quality of the fabric? Comments 0 comments Please sign in to leave a comment.