The CoreGlide is a patented trackless paltform that uses elastic bands attached to the axles which gives the CoreGlide it's rebound properties. The resistance can be adjusted by adding or subtracting bands. The CoreGlide offeres both a short and a long travel setting for specific exercises. No only is the CoreGlide is a great device to use for rehabilitation but also develops the body's core. Used by many in multiple sports like Snow Skiing and Ice Hockey to name a few.