Bests & Worsts Reviews from Amazon

Regretably having lived at high altitude for many years and having had an issue with low blood oxygen saturations I have had several pulse oximeters in the last 20 years. While not an issue now at sea level, I did need one for accurately checking pulse during work outs. I am very familiar with what my average stats are, particularly my heart rate. While there may be slight variation between readings on the left and right hand, there should not be much of any between the middle finger and pointer or ring finger on the SAME hand. Initially checked this on the left hand middle came up with a reading of O2 that was in the low 80s and pulse in the mid 90s. As I know my resting pulse rate is always between 60 to 70, I immediately moved the device over to the next finger where the readings came out with O2 in the mid 90s and heart rate in the low 60s. I tried several more times over the course of an hour and consistently got readings taken at the same time under the same conditions which were so far apart that it confirmed this device simply does not work and should not be trusted for accurate results. In terms of features the results can only be read from one direction, which is not a big deal for me as I am very familiar with these devices but having had ones in the past where like a phone or tablet the orientation changes based on how the device is being looked at, this is a feature which most people would far prefer. Maybe I got a dud, but where there is one rotten apple there is typically others.