Like most sleep soothers, this one emits the white noise that research shows is soothing to babies. And like most soothers, this one uses an automatic shut-off timer, operating for 20 minutes and then switching off to save the battery. But some sleep soothers actually wake the baby when they go silent because of the change in sound. With this soother, if the baby wakes again, the sound goes on for an additional 20 minutes, which helps the baby go back to sleep. There are five soothing sounds to choose from, all of them featuring the sound of a resting heartbeat. This cuddly plush also features a soft, comforting nightlight. Safely attach it to a crib, car seat or stroller with the velcro tail. And when this little sheep needs a bath, just remove the control pad and throw it in the washing machine.