About this product

1、4pcs HSS constructed drill bits for drilling holes with screw sizes #6,#8,#10 and #12

2、Special designed steel counter sleeve countersinks or counter bores hole. Drill and countersink for wood screws without changing bits

3、Adjustable counter sleeve depth with hex wrench. 6.35mm standard hex shank is fast change compatible

4、Drilling length can be adjusted for various length screws simply by loosening and tightening the setscrew

5、Suitable for drilling workpiece with the hardness below 25HRC, such as for carbon steel, sheet iron.plate, insulating plate, PVC plate, wood board, etc. Use on a drill machine with chuck or connector

These high strength HSS constructed drill bits are perfect for drilling workpiece with the hardness below

25HRC, such as for carbon steel, sheet iron plate, insulating plate, PVC plate, wood board, etc.