| 29 / | HD | METAL WORKING |
| 592 | DF | METHOD OF MECHANICAL MANUFACTURE {54} |
| 888 | DF | .~ Prime mover or fluid pump making {12} |
| 888.09 | ![]() | .~.~ Connecting rod making {2} |
| 888.091 | DF | .~.~.~> Including metallurgical bonding |
| 888.092 | DF | .~.~.~> Including metal forging or die shaping |