The baby deedee sleep nest is a quilted wearable duvet blanket for babies 0-36 months. Designed in a comforting cocoon-like shape to help baby feel cozy and secure, it's the perfect transition from the womb or swaddling stage. Unique shoulder snaps make it easy to place baby into the sleep nest, even while sleeping, in just 2 easy snaps. Small is suitable for babies 0-6 months and 10-18 lb. Medium is suitable for babies 6-18 months and 16-26 lb. Large is suitable for babies 18-36 months and 25-35 lb. Winter weight TOG 2.5