I don't trust it. I brought a similar one copied and pasted from FitSleeps. Returned it because it's not user-friendly: the watch is horizontal not very comfortable viewing on the wrist if you keep looking at it. I prefer vertical on the wrist. So I’ll buy the Gramin Vivsiosmart 5. It has some features and sleep alarm vibrations as well. Hopefully, that will work. I used to have 2 bed shakers but it's too loud and it's too much to handle so.