Review on Kori Cryosphere Cold Massage Roller Ball: 6-Hour Cold/Hot Relief, Rapid Recovery, Inflammation Reduction – Removable Ball, Ice Roller, and Myofascial Release – Perfect Massage Gifts by Zaine Davis

This little magic ball has helped me get rid of knots and pain many times since its introduction. No need to refrigerate as it stays EXTREMELY cold on its own (and I live in Arizona). I even have to put a sheet or cloth between my skin because it's so cold on the bedside table right now. It's a bit difficult for me to keep it warm, but if I want to use it warm, I've found that leaving it in the sun is better than warm water. Keeps warm enough for my purposes so I can use it cold or warm.