T.M. DESIGNWORKS Case Saver/Sprocket Cover - Black - Yamaha YCC-YFZ-BKCase Saver Sprocket Cover Black Yamaha Composite machined case protection with integrated sprocket cover, Designed to help protect the engine case from chain derailment, Large cutouts to reduce mud and dirt build up, Accepts one size larger sprocket than stock, Includes hardware, FIM approved, Made in the USA, USA patent issued. Pat # D621,417 S. International Patent # 1706755.