The Therapy in Motion Spikey Massage Balls are a must have for both active/non active individuals. The ergonomic, spiked design helps promote blood flow and thus improve circulation to injured areas. Regular use can help relieve muscle tension and tightness whilst encouraging the release of toxins. The lightweight and small design allows the balls to be used to pinpoint precise trigger points to ease tension and promote relaxation. Can be widely used for a variety of injuries, in particular; plantar fasciitis, achilles tendonitis, hip pain, sciatica and back pain. For this reason they are used extensively in physiotherapy, yoga, pilates and injury rehabilitation centres. Available in two different sizes; Size: 7cm diameter. Weight: 50g. Colour: Red Size: 10cm diameter. Weight: 140g. Colour: Blue