Blackspire super pro chainring fc9000fc6800this quality cnc machined chainring has been designed with modified shift gates to increase shifting performance this chainring also has strategically placed stainless steel pins which further increase shifting accuracy featuresbolt circle diameter 104mmspeed 10 and 11 speed compatiblematerial cnc 7075 t 6 anodised aluminiumbuyblackspire componentsfrom chain reaction cycles the worlds largest online bike store