Version:
Spiral fluted counterbore. The pilot ⌀ matches the intended purpose:
f − for through holes fine quality to DIN ISO 273.
m for through holes medium quality to DIN ISO 273.
Application:
For counterboring socket head screws DIN 912, 6912, 7984, and cheese head screws ISO 1207 (DIN 84).
Note:
For suitable reducing adapters for tools with MT shanks see
No. 343000-343530.