| 464 / | HD | ROTARY SHAFTS, GUDGEONS, HOUSINGS, AND FLEXIBLE COUPLINGS FOR ROTARY SHAFTS |
| 18 | DF | FLEXIBLE COUPLING BETWEEN FLUID-CONDUCTING ROTARY SHAFTS (E.G., COUPLING BETWEEN SECTIONS OF DRILL STRING, ETC.) {2} |
| 20 | DF | .~ Including member deformable by relative movement between shafts {1} |
| 21 | | .~.~ Member is coiled spring |