the making, on the magnetic material and the insulating material 8, of an insulating layer 8 having, at {TAIL ~ its center}, a part M which has no insulating material and leaves {HEAD ~ the magnetic material} free 
the making , on the magnetic material and the insulating material 8 , of an insulating layer 8 having , at { TAIL ~ its center } , a part M which has no insulating material and leaves { HEAD ~ the magnetic material } free
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH