I have it on my garmin and it seems pretty useless. My oxygen level while I sleep has more to do with how tightly I'm wearing it that night than anything else.

I have it on my garmin and it seems pretty useless. My oxygen level while I sleep has more to do with how tightly I'm wearing it that night than anything else. It also drain the battery fast so I just disabled it. I have a real finger-based one bought during COVID that I trust more.