Owlet dream sock 3rd generation baby sleep monitor -tracks live pulse -oxygen levels -quick notifications to phone through app of babies information. Warning alerts notified if levels are low. Socks are slightly discolored (can be machine washed). Owlet powers on, connects to WiFi, and measures readings. Comes with 2 size socks for each foot. View and track your baby’s pulse rate, oxygen, wakings, and sleep trends from anywhere and in real-time via the Owlet Dream App