... 4.ISO9001:2008 T45 MF rod length 3660 :Our company can offer many kinds of drill bits, including chisel type bits, ... , coal cutting, tunneling, rock cutting in quarrying.T38 extension drill rod,length from 1220mm,1525mm,1830mm,3660mm to 6095mm.T45 extension ... drill rod,length from 1220mm,1525mm,1830mm,3660mm to 6095mm.T51 extension drill rod,length from 1220mm,1525mm,1830mm ...