... long working life 2.over 30 years experiences 3.fast speed 4.reasonable price Core Bit ... BitLarge SeriesCore BarrelsTEW, TAW,TBWRX-RWT2-7645mm2-3/4x3-7/8EWT,AWT,BWT,NWT,HWTEX-EWT2 ... 1/2AWF,BWF,NWF,HWF,PWFAX-AWT2-10166mm6x7-3/4NWD-4,HWD-4BX-BWT2-11676mm3-1/ ... 3,BWC-3,NWC-3,NX-NWT2-13186mm4-5/8x3AQ,BQ,NQ,HQ,PQPX-PWT2-146101mm5-3/4x4NQ2,HQ2SX-SWT6-76116mm7-3/4x5-7/8BQ-3,NQ-3,HQ-3 ...