This odd device in the form of a fugly watch is for those who sweat a lot during a deep sleep. It’s worn on your wrist or ankle, usually with comments from your other half like, “What the hell is that?” or “How much of OUR money did it cost you strap that ugliness to your ankle?”. Which is followed by something being thrown at you and you sleeping on the couch.
The idea is that it vibrates and wakes you up when it detects you sweating during sleep. I guess it doesn’t occur to some people to sleep without blankets. And doesn’t your body naturally wake you when you are too hot? I’m calling BS on this device and if you buy it your wife should knee you in the nuts.