Designed to fit 4-arm 110 Asymmetric BCD Shimano Road Cranksets. Its proprietary design has an ovality of 10% and a timing of 112 degrees after top dead center which provide the beneifits of an oval ring such as greater rear wheel traction without the traditional downsides of oval rings. These rings feature the patent pending Drop-Stop asymmetrical tooth design for the best in wear life mud clearance and chain retention.