Headgear container (6)
I believe the answer is:
hatbox
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">headgear container</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 hatbox that I've seen before include "Headgear container" , "Milliner's container" , "Ten-gallon container maybe" , "Container for headwear" , "Case for toppers" .)