100% cotton exterior quilted interior WINTER WEIGHT - 2.5 TOG The sleep nest is a quilted blanket for babies and toddlers. A sleep bag for baby, designed in a comforting cocoon-like shape to help feel cozy and secure, it's the perfect transition from the womb or baby swaddle sack. Unique shoulder snaps make it easy to place your infant into the baby sleep bag, even while sleeping, in just 2 easy snaps. Medium is suitable for babies 6-18 months and 16-26 lb *needed something for very tall baby so she could still stretch out and this was PERFECT throughout the winter!