Adamson B10 Aqua Cooling System - Twin 75” L x 39” W - New - 100% Cotton Mattress Cooling Pad for Night Sweats - Water Cooler Ideal for Hot Sleepers - 5-Year Assurance

Those things cost pennies. And as others have said, someone who doest suffer from sleeping hot/cold aren't gonna see much of a difference if any. You'd probably be better off looking for YouTube videos of people keeping track of their data. Also, if I was gonna buy one of these 8 sleep would be the one I stay away from. Oh and one last thing, If I was buying something to knock a few temperatures off to see if I slept better it would be something like this https://a.co/d/08sDx8r4. I have one and they work pretty good. So much they'll get me too cold but I want something more automatic that just has more finely tuned controls.