Twist Drill Bit Countersunk Screw Bit Drill Rod Screw for G10 Micarta Brass Feature: This kind of drill is used for DIY tools, sinking the screw higher than the shank, and will not scratch your hands after using the screw. Production process: CR12 mold steel heat treatment 55 degrees, made by wire cutting. Use: Put the twist drill through the hole in the sleeve. Only suitable for Wood, Micarta, G10, carbon fiber, resin plastic, cow bone antlers, turquoise, aluminum, brass. Materials with hardness below 30 degrees. Specification: Size description: For example 5.1X8MM 5.1 is the screw diameter (that is, the diameter of the shank hole) 8MM is the nail head diameter (nut diameter, countersunk head diameter) The 5mm shank hole is suitable for the following: Total length: 19mm Screw length: 14 Screw diameter: 5 Recessed head diameter: 8 Countersunk head thickness: 2.5 Topic: M4 Package included: 1*Twist Drill Bit Notes: 1. Not suitable for materials with hardness higher than 30 degrees. 2. Hand drill is unstable, please use bench drill operation. 3. The tools sold in this shop are all produced by our own factory, not original (Genuine) parts.