1. We are specially to cutting granite over 15years in China. All of our granite export to the international market. 2.Our diamond drill bit are suitable for wide range of geological formations from the softest to the hardest rock, widely used in all kinds of drillings for prospecting, water and electricity building and construction industry of road , railway ,bridge and building taking out core examine stake . 3. High quickly drill speed and long time drill life. 4.Materials: super man-made diamond. Copper powder and so on. Size: Size Available: 1. A-Gauge Core Bits: AQ, AQ-RSG, AWG(AX), AWM, AWT, LTK48 2. B-Gauge Core Bits: BQ, BQ-RSG, BQ-2.400, BQ3, BWG(BX), BWM, BWT, LTK60, TBW 3. N-Gauge Core Bits: NQ, NQ-3.032, NQ2, NQ2-RSG, NQ3/NQTT, NQ3-RSG, NQ3-3.032, NMLC, NWG(NX), NWM, NWT, TNW 4. H-Gauge Core Bits: NQ, HQ-RSG, HQ-3.830, HQ-3.895, HQ3/HQTT, HQ3-RSG, HQ3-3.380, HQ3-3.895, HMLC, HWF-Long, HWF-Short, HWG(HX), HWT 5. P- Gauge Core Bits: PQ, PQ3, PWF-Long, PWF-Short 6. S- Gauge Core Bits: SWF-Long, SWF-Short 7. U- Gauge Core Bits: UWF-Long, UWF-Short 8. Z- Gauge Core Bits: ZWF-Long, ZWF-Short 9. T, TT, T2 &TB Series Metric Core Bits: T36, TT46, T2-46, TB56, TT56, T2-56, T2-66, T2-76, T2-76 coreline, T2-86, T2-86 coreline, T2-101, T2-101 coreline 10. T6 Series Metric Core Bits: T6-76, T6-86, T6-101, T6-116, T6-131, T6-146 11. T6S Series Metric Core Bits: T6S-76, T6S-86, T6S-101, T6S-116, T6S-131, T6S-146 12. B Series(ISO3552-1) Metric Core Bits: B36, B46, B56, B65, B76, B86, B101, B116, B131, B146 13. Chinese Standard Metric Core Bits for Single Tube Core Barrels: Ï?36, Ï?46, Ï?56, Ï?59, Ï?75, Ï?91, Ï?110, Ï?130, Ï?160, Ï?170, Ï?219, Ï?275 14. Chinese Standard Metric Core Bits for Double Tube Core Barrels: Ï?56, Ï?59, Ï?75, Ï?91