Feature: 1. Made of high speed steel, having the characteristics of strong cutting performance and long service life, which can well meet your needs 2. The blade is hardened and honed, so the drill bits are very incisive, and has the design of no chattering vibration 3. The staggered cutting teeth ensure the glossy and clean of the fine countersink and hole, giving you a good experience 4. Very suitable for drilling holes in alloy steel, wood, nonferrous metals, cast iron and hard plastics 5. Mainly used in mechanical processing, woodworking, to help you easily complete drilling work and improve work efficiency Specification: Item Type: Drill Bits Sets Material: High Speed Steel Drill Diameter: Approx. 1-6mm/0.04-0.24in (interval 0.1) Purpose: Suitable for Drilling Holes in Alloy Steel, Wood, Nonferrous Metals, Cast Iron and Hard Plastics Applicable Scenarios: Mechanical Processing, Woodworking. Package List: 51 x Twist Drill Bits 1 x Iron Box(Red or Blue Random)