Bests & Worsts Reviews from Amazon

Just compared this to another inexpensive finger oximeter I purchased a few months ago. Both take maybe 15 seconds for readout and this one provides about the same reading as the other; no more than 1 digit off (when one said 98% O2 saturation, the other might have said 97% or 99%). Close enough for my purposes. From a study I ready somewhere, these inexpensive finger pulse oximeters are generally accurate when you're reading someone that's between 90% and 100% saturation. A Nonin Onyx professional quality ($186.00) is certainly appropriate in a medical setting when patients may be dropping below 90% but I think these inexpensive ones would be enough to let you know if you should be getting medical attention.