... 520J 3Diamond thickness is increased to 2.0 PDC cutters/diamond compact/PDC1PDC for geology exploring and mining field bits seriesAbrasiveness 1:300,000 ... higher than the old series. 3. Wear resistance is a bit higher than old series. 4. Heat resistance is improved ... 1913,1916PDC for geology exploring and mining field bits 1004,1204,1304,1308,1504,1508,1604,1608,1908The advantages of the new cutter is ...