Thanks. In a previous comment you said that “The oxymeter beeped and woke me up.” Is this the same oxymeter? I read the FAQ for the FL350 and it doesn’t have an alarm.
I double checked and the one I use is an old model (FL100) that appears to have been discontinued. The FL350 mostly resembles it, though it appears you are correct that the FL350 does not have an alarm. My apologies for the misdirection.
If you can spend more, I'd suggest the wrist type. The fingertip can be a little uncomfortable being clamped to your finger all night.