Diamond bits and diamond coring bits are necessary tools in oil drilling operations , PDC bits , polycrystalline diamond bits and natural diamond bits. 
Technical parameters and specifications
 
| Bits size(in) | 
Diameter tolerance(mm) | 
Thread connection API |  
| 4 5/8  | 
0-0.38 | 
2 7/8REG(Pin)  |  
| 6 | 
3 1/2REG(Pin)  |  
| 8 1/2  | 
0-0.51 | 
4 1/2REG(Pin)  |  
| 9 5/8  | 
0-0.76 | 
6 5/8REG(Pin)  |  
| 12 1/4  | 
6 5/8REG(Pin)  |    |