Sonic Bomb alarm clock from amazon. $42. Put the vibrate part between mattress and boxspring. Sound can be disabled or turned to max. Good luck sleeping through that

Sleep number 100 here. Belly sleeper I prefer “very firm”. Husband is sleep number 32 , back & side sleeper and wants all the fluff, this is why we have sleep number that was purchased 10 years ago and still works.

Edit: the sleep number mattress we bought was third cheapest. Just enough to get the app access to the firmness adjuster.