A set of professional bimettal holes for drilling large holes in metals, sheets, shapes and pipes Also perfect for drilling in plastic, furniture slabs, structural sandwich panels and resins Recommended for professional use in industry, websites and workshops This set, due to the selection of elements, is especially dedicated to the electrical installation industry The holes are made of the highest quality materials - HSS M 3 high -speed steel teeth The progressive teeth profile increases aggressive cut The set includes a variable teeth of 4-6 TPI (TPI - the number of teeth per 1 inch, i e. 25. 4 mm), which perfectly increases work efficiency.