Milwaukee Diamond Bits are designed for fast, efficient coring in a wide variety of concrete, including poured, steel reinforced and pre-stressed, as well as asphalt. Our PREMIUM grade bits are designed to offer exceptional life and conform to the Diamond Core Drilling Manufacturers Association standards. A 14 inch tube length is standard. The bit incorporates a threaded back for attachment to the Diamond Drill Motor. The Diameter of this bit is 3 inchs and the thread is 1-1/4-7.