... reaming shellΦ56,Φ59,Φ75,Φ91,Φ95 AQ,BQ,BQ3,NQ,HQPQ,PQ3Electroplated diamond core bit description: ModelRegular sizesSuited stratumInternational ... abrasiveness. Good at drilling "Slippage" strata.2. The matrix has a high abrasion resistance, and also working good in slightly higher ... shellΦ56,Φ59,Φ75,Φ91,Φ95 AQ,BQ,BQ3,NQ,HQPQ,PQ3 NQ/HQ Impregnated diamond core bit/Electroplated Diamond Core Drill ...