A ball for massaging the soles of the feet and releasing the fascia. Two balls are connected and it is just the right hardness to massage the foot of a figure skater. With this size, you can carry it in a bag for cars, trains, airplanes, etc. If it gets dirty, you can wash it and use it cleanly. It's the most needed tool for foot conditioning for figure skaters who struggle to stand on sharp blades. It is also very good for calves.