Replacement tread for s works mtb carbon outsoles with replaceable lugs features mtb lugs come with heel ball and toe pieces included sold in pairs includes screws includes spikes specialized part number reference 6110 9170 shoe lugs 38 39 6110 9171 shoe lugs 40 41 6110 9172 shoe lugs 42 6110 9173 shoe lugs 43 44 6110 9174 shoe lugs 45 46 6110 9175 shoe lugs 47 48 for a comprehensive shoe spares guide please click this link shoe guide