{HEAD ~ The second pulley} and the tool lie on {TAIL ~ the same rotation axis}, so that when the head is in a position rotated at an angle of 90° to the longitudinal axis of the instrument, both pulleys lie in the same plane 
lie on
{ HEAD ~ The second pulley } and the tool lie on { TAIL ~ the same rotation axis } , so that when the head is in a position rotated at an angle of 90 ° to the longitudinal axis of the instrument , both pulleys lie in the same plane
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH