... near future Milled tooth bits1,Soft formations(114-117)These bits are designed to drill the softest formations such as ... 3,Medium to hard formations(213,214,215,217)These bits are designed to drill formations such as hard sandstone, ... GA625GY7 5/8 more information: Model6-26( inch) TypeTricone bits, Steel tooth bits, PDC bits Applicable water well, oil field, construction, geothermal, directional ...