Childrens/Kids Thomas the Tank Engine Bedding Duvet Cover and Pillowcase (Twin Bed) (Blue) Please note: This product is a UK import, the sheets supplied are slightly smaller than the standard US duvet size, it will fit but the duvet may fold at the edge when covered. This is not a comforter but sheets for a duvet. Childrens Thomas the Tank Engine Team Steam design single duvet set. Perfect for your childs bed. Single duvet set includes a duvet cover and one pillowcase.