Features: Made of high hardness metal, they are durable and superior drilling performance. Center Drill bit perfect for hinges, handles, drawer slides, woodworking . Suitable for professionals and woodworking enthusiasts. Efficient and accurate positioning; Double-sided hole design fast and automatic discharge sawdust from the hole on both sides; Specifications: Material:Metal Includes:5/64",7/64",9/64",11/64",5mm,13/64",1/4"; 5/64" Drill Bit Opening Diameter:Approx.2mm/0.08in,Using 2.2-2.8mm/0.09-0.11in Screws; 7/64" Drill Bit Opening Diameter:Approx.2.8mm/0.11in,Using 3-3.5mm/0.12-0.14in Screws; 9/64" Drill Bit Opening Diameter:Approx.3.5mm/0.14in,Using 4-4.5mm/0.16-0.18in Screws; 11/64" Drill Bit Opening Diameter:Approx.4.5mm/0.18in,Using 5-5.5mm/0.2-0.22in Screws; 5mm Drill Bit Opening Diameter:Approx.5mm/0.2in,Using 5.5-6mm/0.22-0.24in Screws; 13/64"Drill Bit Opening Diameter:Approx.5.1mm/0.2in,Using 5.6-6.1mm/0.22-0.24in Screws; 1/4"Drill Bit Opening Diameter:Approx.6.3mm/0.25in,Using 6.8-7.3mm/0.27-0.29in Screws; Note: Please allow 1-2cm errors due to manual measurement,please make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 8xSelf Centering Drill Bits 1xHex Key