... premature wear of the matrix. Surface-Set Diamond Bits are set with a singular layer of natural or ... the face of the bit. The diamond set design ensures sufficient overlap to prevent premature wear ... of the matrix.1,Surface-Set diamond bits are primarily recommended for use in ... Size AvailableQ series AQ, ,NQ, HQ, PQ (Front end & Back end Type)T SeriesT36, T46, T56, T66, T76, T86WF ...