Wellue Fingertip Blood Oxygen Saturation Monitor with Alarm $16 at Amazon
Amazon with Sensebody has the Wellue Fingertip Blood Oxygen Saturation Monitor with Alarm (PC-60F) for $20 - $4 off with coupon code
CGBEYIU5 [Exp 8/16] =
$16 with free shipping on $25+ or with Prime.
Includes 2 x AAA batteries.
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