The Kor stone, I believe, itself is pretty unnecessary; it's a thin sheet of paper-looking rock that is placed in the bottle. Supposedly while you drink, you should read the motivational message, but when I drink I'm not looking up. But other than that, this is a very sturdy bottle. The area where you put your lips is very nice... feels good. Also, there is a layer of rubber which helps the bottle to sit well on surfaces. Lastly, the holder feels unbelievably comfortable.

ZohaibQazi

USA