299 / | HD | MINING OR IN SITU DISINTEGRATION OF HARD MATERIAL |
1.05 | DF | AUTOMATIC CONTROL; SIGNALING OR INDICATING {4} |
1.4 | DF | .~ Of hard material disintegrating machines {3} |
1.6 | .~.~ Sidewall working {1} | |
1.7 | DF | .~.~.~> Of advancing material handling means or roof support |