MTE D-2 (DOUBLE INSERT) : Double insert type indexable threading end mills for various internal or external threading
COOLANT                                            
  DesignationapDdD2L1LShankkgGICATGIREMgiic
  MTE D20.0-2-W20-14 14.0020.0020.0016.0041.0093.00W 0.206198631 0
  MTE D30-2-W25-21 21.0030.0025.0024.0052.00108.00W 0.406198632 0
  MTE D40-2-W32-30 30.0040.0032.0030.0070.00130.00W 0.706198633 0
  MTE D50-2-W40-40 40.0050.0040.0038.0078.00153.00W 0.006198634 0

Minimum bore should be one-third larger than D (diameter)
All end mills are equipped with a bore for internal coolant