Know your baby is okay: Track your baby's heart rate and oxygen levels while they sleep using clinically-proven pulse oximetry, and be notified if something appears to be wrong. Have complete peace of mind knowing you can keep track of your baby's heart rate and oxygen levels from anywhere. Proven: Pulse oximetry allows you to track your baby's oxygen level and heart rate. Real Time Tracking: Monitor your baby's readings directly onto your smartphone. Be alerted instantly if oxygen levels drop below the preset threshold. State of the Art App: Using Owlet's app, you can receive notifications and stream real-time heart rate and oxygen levels on your phone. Our Promise: Love it or return it within 30 days for a full refund. We ensure that all our products, including the Owlet Smart Sock are BPA free, latex free and lead free.