Wellue O2Ring Overnight Oxygen Saturation Tracker $103 at Amazon
Amazon with getwellue has the Wellue O2Ring Overnight Oxygen Saturation Tracker with Notification for Low O2 Level and Heart Rate, Free APP PC Report for Sleep Insights for $162 - $10 off coupon
(check green "Save coupon" box) - $49 off with code
7284UK69 [Exp 11/21] =
$103 with free shipping.
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