Detailed Product Description Made of Cr carbon steel with industrial grade carbide tip. Milled Round Flute for quick, easy debris removal. For use with rotary or roto-percussion drills. For drilling in concrete, rock, stone, masonry, marble and breeze block. Dia.3-26mm/1/8' to 1' Black Oxide, Zinc Plated, Black & White, Nickel Plated, Chrome Plated can be available.