The Yantra flex is designed to stimulate the acupressure points on the feet, following the principles of traditional chinese medicine. This can help to relieve stress and anxiety, sending impulses to the brain through the physical stimulation of the feet. Helping to improve blood circulation, the Yantra flex massages can be reversed to give a different experience. The dark blue flex is super lightweight, anti-slip treated and water resistant. If suffering from any medical problems or skin conditions that may be affected by using the Yantra flex, consult your doctor before using it. Stop using the Yantra flex if you have dizziness or extreme discomfort that you think may be caused by using the Yantra flex. Consult your doctor if it persists. Not recommended for use if pregnant. Always read the user instructions carefully before use.