... 7/8"--17" API&ISO9001:2008 Brand new MOQ:1 piece API 8 1/2" 5 Blades New PDC Bits for Oilfield Well ... , TCI rock bits, oilfield bits and so on .Specification: diameter from 3-1/8” to 17”.There are different PDC (polycrystalline diamond ... , marble, metamorphic schist (For hard, low abrasive formations)2. Gneiss, Diorite, Basalt (For hard and abrasive formations)3. Quartz, ...