... of lips: flat-bottom,circular,ladder-teeth,serration,pointed teeth,round teeth,angle teeth,ladder, and ladder with end spray or side spray ... .B series diamond drill bits are made of premium diamond. Both efficiency and ... .B7#,B8# ——applicable to stable,vitreous,low abrasive,hard and slippery stratum.B9#,B10# ——applicable to stable,vitreous,weak ...