i know. i threw in onto the concrete patio and it shattered. i then ran outside. i grabbed the rock (or what was left of it) and threw it down as hard as i could multiple times. a month or so later, after we lost the cord for our radio, my brother said that he had found it. i saw the zoo med logo on it and threw it away.
I have dedicated my life to teaching others on the dangers of a hot rock heating system for anything but a totally inefficient snow melter or a totally efficient peice of garbage. just kidding about the "i have dedicated my life part