Prime members only. Amazon with Wellue-US has the Wellue BabyO2 S2 Oxygen & Heart Rate Baby Monitor for $200 - 5% off coupon (check "Save an extra" box) - $50 off with coupon code FZSCHMZP [Exp 12/5] = $140 with free shipping. The base station and app will alert you to abnormal O2 levels, abnormal heart rate, or baby's motion.