Wellue Pulse Oximeter Fingertip Blood Oxygen Saturation Monitor $24 at Amazon
Amazon with Sensebody has the Wellue Pulse Oximeter Fingertip Blood Oxygen Saturation Monitor with Batteries & Lanyard for $40 - $16 off with coupon code
U3MR27UR [Exp 2/7] =
$24 with free shipping on $25+ or with Prime.
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