Warming and Cooling stones

Describe an invention in your world that helps people with disabilities.

Warming Stone:

Terrains are made of many races and not all can handle the extremes. The Reptilians, not being true cold blooded, have a very difficult time with raising their body temperature. They can even die if their body drops below 30C.
The Warming Stones are such beautiful red people may want to wear them as jewelry. The Stone's intended purpose is to warm the body. By whispering the power word for "warm" the stones heat to 37C in just a few minutes. It can maintain this temperature for days at a time. These stones even come in tiny torus or doughnut shaped version that can be sewn into armor and clothing, warming even the most frigid of hearts.

Armor Craftspeople have been adding them to the clothing of our Reptilian friends. It is wonderful that Z'An-Ya has blessed us with such magic that there is no place off limits for any of the inhabitants of Terra.

Cooling Stone:

While the Arctic Elves and Dwarves have a tendency to go berserk if their body temp rises much above 32C. They also have the special trait known as “Not Dead till Warm and Dead” when falling into ice water or being gored by a polar bear. If they drop body temp to freezing fast enough they will sleep until they can be healed. Now you know why the Dwarven armies of the Arctic fight in nothing but a kilt it is not just to intimidate their enemies but a matter of survival (ok half naked Dwarves in sub zero temperatures are pretty intimidating in their own right!)

There have been rumors that the Arctic Elves and Dwarfs have an improved Cooling Stone that act automatically. They are sewn into their armor, freezing their body just before death.