Most injuries don't occur through extreme activity. They happen during the everyday motions that add wear and tear to our bodies over time. The GRID STK foam roller is the world's first hand-held roller wrapped in a 3D-textured surface. The bumps and ridges of the roller mimic the feeling of a message therapist's hands, which in turn promotes blood and oxygen flow. The roller is water-resistant, easy-to-clean, and totally portable.