The Kurt Kinetic Turntable Riser Ring is an absolute nessesity for the Rock and Roll Trainer. It is designed to meet the needs of riders who want a level bike when they train. The Riser Ring is adjustable to four heights to simulate flat roads on almost any bike. Sits under front tires for a stable ride, no matter how hard or long the workout, with the addition of a swivel base allowing the front wheel to move freely and help a rider perfect his technique.