The Convertible Air Woombie® 2 in 1 Swaddle Sleepbag. It is a one-step vented self-soothing swaddle with over 20 awards for design and innovation. Fabric is light and breathable, ergonomically shaped with a ‘hip healthy’ design. Arms in or out depending upon baby’s needs and milestones such as rolling. Mild compression mimics the sensation of touch and an arms-free interior allows for self-soothing in the Hands Over Heart™ recommended sleep position. One step swaddling with multi-dimensional stretch and 2-way zipper to prevent unraveling throughout the night.The perfect stretch for baby’s needs. Cotton/Spandex blend. Dress baby accordingly underneath depending upon season and nursery temperature. Patented Design.