A lot can happen while your child sleeps, but a traditional baby monitor can only tell you so much. By tracking your baby’s heart rate and oxygen level, the Owlet Smart Sock goes beyond what you might be able to see or hear, so that you can really know if your baby is sleeping soundly or if they need you. Other baby monitors require you to be constantly watching your baby on the monitor screen to notice if something goes wrong. The Owlet Smart Sock is the only monitor that uses proven technology, designed to proactively notify you if your baby's heart rate or oxygen levels fall out of range.