Luvable Friends Fitted Crib Sheet is made of pure knitted cotton, which makes it soft and durable. These sheets are designed to provide a soft feel that babies will enjoy feeling against their tender skin. With fully elasticized bottoms and deep pockets that let them fit standard crib mattresses securely, these sheets help provide a cozy and comfortable sleep along with a snug fit. Designed especially for a longer wear, these sheets are machine washable for no hassle cleaning. Made of 100% Cotton Flannel, these sheets will help keep baby warm and cozy in the winter or during the summer with the air conditioning.