To create advantageous constructional conditions, it is proposed that in its nose piece the optical spectacle insert should have a through hole for {HEAD ~ at least one plug in projection} of {TAIL ~ an attachment plug} engaging in a plug in recess of the forehead side portion of the sunglass frame  
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To create advantageous constructional conditions , it is proposed that in its nose piece the optical spectacle insert should have a through hole for { HEAD ~ at least one plug in projection } of { TAIL ~ an attachment plug } engaging in a plug in recess of the forehead side portion of the sunglass frame
OTH OTH OTH OTH OTH 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 HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH