... cross bits, thread button bits, retrac button bits, extension rods, shank adapter, coupling sleeve, etc.All the products adopt ... drill small holes. Because of the integration of the rods and bits, the integral drill rod can be metched directly ... coupling sleeve, these advantages avoid the wastage of energy, and improve the drilling efficiency remarkably. DimensionsPart onL Dmmftinmmin150 61721/32H19 ...