ATOPLEE 4pcs Steel Wood Countersink Debur Deburring Tool Deburing Set Hole Countersinker This 4 piece Countersink and Deburring Tool Set is ideal for cutting through metal, wood and plastic quickly and easily . This is hands down, the best countersink I have never used Material: High speed steel 4241 Size(four type): 2-5mm,5-10mm, 10-15 mm, 15-20mm Length:2-5mm:4.5cm; 5-10mm : 4.7cm ;10-15mm : 6.2cm ;15-20mm: 8.2cm Package Included: 4 x Countersink and Deburring Tool