For strengthening weakened or injured hand, finger, wrist, and arm muscles. Completely washable in warm water. Contoured to fit comfortably into hand. Can be used to help reduce stress as well as increase strength and flexibility. Compressible synthetic rubber material leaves no messy residue. Returns to its original shape when released. X-Soft has slow recovery, great for individual finger and thumb strengthening. Colour coding simplifies progressive rehabilitation.