Blackspire super pro cyclocross chainringsthis 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 9 and 10 speed compatiblematerial cnc 7075 t 6 anodised aluminiumbuyblackspire componentsfrom chain reaction cycles the worlds largest online bike store