The barrier is furthermore spaced radially away from {TAIL ~ the central portion} or stem of {HEAD ~ the insulator} over at least a substantial part of the inner periphery of the barrier 
The barrier is furthermore spaced radially away from { TAIL ~ the central portion } or stem of { HEAD ~ the insulator } over at least a substantial part of the inner periphery of the barrier
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH