a plurality of electrodes in {HEAD ~ an array} and adapted to be in {TAIL ~ electrical contact} with the body 
a plurality of electrodes in { HEAD ~ an array } and adapted to be in { TAIL ~ electrical contact } with the body
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH