STADEA diamond drill bit hole saw core drill bit 1 1/2" or 38 MM for Granite Marble Concrete Stone Masonry coring Stadea Professional Grade 1 1/2" or 38 mm Diameter Wet or Dry diamond drill bit hole saw core drill bit Wet Dry Drill/Core through Granite, Marble, Tile, Stone, Porceline, Concrete, Masonry with precision Segment Height 9 MM, Width 16 mm, Thick 3.0 mm Optimal RPM 900 Arbor 5/8" 11 T