Ultegra 9-speed FC-6500/6503 chainringsFor best shifting performance, A-type rings should be used only with A-type rings, and B-type rings only with B-type ringsItem SpecificationsColorSilverMaterialAluminumTeeth39teethBolt Pattern5-BoltChainring BCD130mmRing PositionInnerChain Compatibility9-SpeedDefined ColorSilver