Description 2 Spiky Massage Balls for massage, relaxation exercises, hand therapy & reflexology. When to use them Apply in circular motions for a firm massage & to improve circulation. Stimulate muscle reflexes to ease tension & provide relaxation of the body. Size 6cm (orange) How they work Use for a self massage or with assistance to treat back pain, improve circulation, stimulate muscles & ease tension. This 6cm orange massage ball is for massaging the hands & feet. These can also be purchased as part of a set.