For abrasive materials. Tools will drill countersink and finally counterbore a parallel hole. Designed to receive plug produced by maker Ref. 24 group. The drill diameter sizes are for a clearance hole only.

Specification:
D=12 mm
D2=5.5 mm
C=20 mm
OL=62 mm
Shank Diameter=1/4 inch
Wood screw size= No 10