The Diamond Products BTP8000 8in Premium Diamond Turbo Concrete Core Bit has TPOWL bond segments for general purpose applications with high steel for longest life. Serrated segment design for less surface to surface contact. Highest quality diamond and longest coring life in the medium aggregate concrete with heavy steel. Serrated segment for faster coring. Core Bit Lengths: Standard Core Length = 13in. Note: Any length available upon request. Note: All diameters are nominal. Exact tolerances upon request.