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