Core Bore Premium Black Diamond Core Bit, Use for coring conrete reinforced concrete and masonry, Top performance bit, Offers Best Footage and Speed, Core Length: 13"", 1/2"" to 1-1/2"" = Spline: 5/8""-11 thread, 1-5/8"" and up = Spline: 1-1/4-7 thread, SKU: DMP036