A third form of {TAIL ~ the apparatus} includes a pair of {HEAD ~ conductors} not in mutual contact, but each in contact with a third conductive member when in its rest position 
A third form of { TAIL ~ the apparatus } includes a pair of { HEAD ~ conductors } not in mutual contact , but each in contact with a third conductive member when in its rest position
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH