ITEM NAME:4Pcs Countersink-Drill Drill-Bit-Set Pilot-Holes Woodworking Screw-Sizes Descriptio n Description: Material: high speed steel. High Speed Steel for general purpose drilling in a variety of materials. Features safety collar stop to prevent over penetration and operator loss of stability. Specifications: Material: high speed steel Color as shown Size: 4 piece set (6.8.10.12mm) Package Included: 4-piece drill set * 1 Note: 1.Due to the manual measurement and different measurement methods, the actual size could be slightly different. 2.Please be reminded that due to lighting effects and monitor's brightness/contrast settings etc, the color tone of the website's photo and the actual item could be slightly different. We offer you what you need! 4Pcs Countersink-Drill Drill-Bit-Set Pilot-Holes Woodworking Screw-Sizes.Features safety collar stop to prevent over penetration and operator loss of stability. We'd like to settle any problem in a friendly manner. High Speed Steel for general purpose drilling in a variety of materials.