6-Piece Set 6 most commonly used sizes to meet all your needs. This drill bit set fits most drills on the market today and comes with a portable plastic bag for easy storage and organization. M35 Cobalt High Speed Steel Industrial grade HSS 6542 drill bits, harder than HSS 4241 used in other similar drill sets. These bits also contain 5% Cobalt for improved wear resistance and durability. Full polishing process and 135 degree split point Fully ground helical spline design quickly reduces friction and heat for faster, cooler drilling performance. The 135 degree parting point of the straight handle prevents stepping and the drilling is more precise and faster. Center punch is not required. Multiple Applications Ideal for cutting hard metals such as stainless steel, steel and cast iron, as well as wood, aluminum alloys and other softer metals including tile, concrete, tile, brick, wood, plastic, glass, masonry, etc. Work Efficiently The sharpness of the product is sharp and the drilling efficiency is high. There are sharp serrations in the center of the product, with the help of which the drill can continue to drill horizontally after drilling.