Cap Screw Counter Bore - Metric  HSS 7 pc set  

• 7 Pieces including: M3, M4, M5, M6, M8, M10, M12 sizes 
• Suits counter boring the above sized cap screws
• High speed coated head cap screws
• All shanks are straight.

12mm counter Bore  head 18.40 pilot 13.50

10mm counter Bore  head 16.50 pilot 11.00

8mm counter Bore  head 14.20 pilot 9.00

6mm counter Bore  head 10.40 pilot 6.60

5mm counter Bore  head 9.20 pilot 5.50

4mm counter Bore  head 7.80 pilot 4.50

3mm counter Bore  head 5.90 pilot 3.50

 Counterbore, or counterbore cutters, are drill-bits used to make counterbore holes, which is a way of creating a flat-bottomed extension of an existing hole in a material. The counterbore cutter will essentially create a cylindrical cavity at the head of an already drilled hole. This allows the hole to accommodate flat bottomed screw or bolts so that they sit flush to the surface of the material