At first, I thought that one of the balls seemed somehow warmer. And indeed, it turned out to be the Pneumatit ball. Then, however, it seemed to me that the left hand feels warmer anyway. So I started switching the balls from one hand to another and trying them out until I reached some kind of certainty or decision. How does that feel? It’s not easy to say. Warmer, more pleasant, more lively somehow. It’s difficult to find precise terms for this sensation. In any case, a pleasant difference can indeed be felt with the Pneumatit ball. For whatever reason – currently a friend is visiting as well; I gave him both balls to try too. As soon as he held them in his hands he said: “This one is warmer.” And he was right; it was the Pneumatit concrete.