Each sock set contains 3 sock sizes (1-3). Please note, the updated size 3 has replaced the original size 4. The socks are lead, BPA and latex free.ACCESSORY SOCKS ONLY: Add additional colors or back up socks for your Owlet Smart Sock 2 Baby Monitor (sensor and base station not included). Recommended Sizing Chart SizeAgeWeight1 (newborn)0-1 months6-8 lbs21-4 months8-14 lbs34-18 month14-25 lbs Owlet is not an FDA approved medical device and is not intended to diagnose, treat, mitigate, cure, or prevent any disease or condition. *This is a non-refundable purchase.