a linkage assembly including {HEAD ~ a link} operable to transfer forces between {TAIL ~ a contact arm} and an actuator lever 
a linkage assembly including { HEAD ~ a link } operable to transfer forces between { TAIL ~ a contact arm } and an actuator lever
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH