Assertion: mandible's surface | /r/HasProperty | each arm
Facets:
Source sentences:
text: With the lower jaw thus in the existing closed position, the nuts 158, with the centering guides withdrawn are retightened so that the front surface of the nut 158 clamps each arm 64, 66 against the flange 130d of the associated ball element 130, which is now somewhat off center of the aperture 170.