Black Diamond Core Drill Bit Wet/Dry Granite Concrete Stone Marble Tile.

This Core bit is from the Economy line.  It is a low cost core bit with goo performance.

Diamond Side Protection for Fast Cutting. This Core Bit Works Dry or Wet on Granite, Marble, Travertine, Limestone, Concrete.

  Thread size is 5/8-11 female. This Amazing core bit also has inside wall diamond protection as well as outside protection for Fast Drilling.