Blackspire super pro middle ramped chainring the engineered ring cnc cut from 7075 t6 aluminium modified shifter gates special profiles to allow 910 speed chains to shift hassle free the middle ring is cut from thicker 0190 plate to prevent the chain from falling between the granny middle ring blackspire super pro middle ramped chainring specifications stainless steel pins for better shifting 910 speed compatible 4 bolt buy blackspire component from chain reaction cycles the worlds