A method 1, characterized in that the pattern of openings in the planar element is obtained by stamping {HEAD ~ the openings} in {TAIL ~ the planar element} 
A method 1 , characterized in that the pattern of openings in the planar element is obtained by stamping { HEAD ~ the openings } in { TAIL ~ the planar element }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL