Norseman 190-CN Cryogenic Nitrided Jobber Length Premium drill bits with 3-Flat shanks. These heavy-duty 135° split point drills perform well in very demanding applications. The flats on the shank give positive chuck grip. The drills are ideal for use with hand held drills with keyless chucks. The Ultra-Dex drill index is weatherproof, watertight, and unbreakable.