Protective eyelet (7)
I believe the answer is:
grommet
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">protective eyelet</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for grommet that I've seen before include "Eyelet's metal ring" , "Tube in eardrum to drain and ventilate ear" , "Washer; eyelet" , "Ring shaped to line a small hole" , "Eyelet lining a small hole" .)