| 188 / | HD | BRAKES |
| * | DD | ELEMENTS {6} |
| 219.1 | DF | .~ Beams or beam assemblies {6} |
| 219.6 | DF | .~.~ With movable, reversible or adjustable heads {1} |
| 220.1 | DF | .~.~.~ Pivoted head {1} |
| 220.6 | | .~.~.~.~ Lockingly adjustable {1} |
| 221.1 | DF | .~.~.~.~.~> Yieldably readjustable |