Premium micro twist bit set for professionals - Purpose built for electronics, crafts, jewelry, and watch making - Micro twist bits for mini precision power drills, enabling detailed work on small parts - HSS high speed steel construction for durability and sharpness - Hole sizes from 0.4 mm to 3.2 mm, suitable for a range of small drilling tasks - Compatible with micro precision power drills for precise control and clean results Use scenarios - Electronics: drill tiny pilot holes or component housings on circuit boards with accuracy - Jewelry and watchmaking: create or modify small metal parts, beads, and components with tight tolerances - Model making and crafts: prepare delicate parts and miniature projects that require precise small-diameter holes Material and size details - Material: High speed steel (HSS) - Size range: 0.4 mm to 3.2 mm