Version:
Spiral fluted counterbore with fixed pilot.
DIN 373 / ISO 4206.
Application:
For through hole quality fine (ISO values) to DIN 69.
For socket-head screws to DIN 912, 6912, 7984, and cheese-head screws to ISO 1207 (DIN 84).
Note:
Size 4.6 × 2.4 is not defined in DIN.