Dewalt diamond core bit is design for high speed drilling and long life in a wide range of building materials. For use with diamond drills. Standard 1-1/4 Inch UNC female fitment to allow usage with Dewalt and other diamond drill brands. For use with diamond drills. For dry drilling clean large diameter holes in masonry and stone. D52X1 1/4″ UNC(F)XL500XT3.5MMXW10