The 90° bit countersink set consists of six bit countersinks in dimensions between 6.3 mm - 20.5 mm. 
 
The 90° bit countersink is a tool for making conical offsets or for precise deburring drilling. A hole in metal should always be deburred with a taper countersink, as the edges of the hole are very sharp. This is useful both to avoid cutting injuries and to achieve a flat surface. To be used with cordless screwdrivers that can be found in almost every tool box, whether for the do-it-yourselfer or the professional craftsman.
 
If the screw is to be countersunk into the workpiece, the hole is pre-machined with a countersink. The hole is then drilled out conically to countersink the countersunk screws into the material. In this way, the screw head is flush with the surface of the workpiece. 
 
Features:
- For normal steels, cast iron, iron, sheet metal, aluminium and light metals up to 800 N/mm²
- For use with cordless screwdrivers, rotary handles or ratchets with 1/4'' bit receptacle
- For burr- and chatter-free countersinking, deburring and countersinking
- Best results are achieved with low cutting speeds
 
Standard: DIN 335-C
Material: HSSG
 
90° bit countersink set contains: 
6.3 mm for M 3
8.3 mm for M 4
10.4 mm for M 5
12.4 mm for M 6
16.5 mm for M 8
20.5 mm for M 10