During the regime of cloistered government in the end of the Heian period, Court caps were thickly lacquered so they would not lose their shapes, and ei was separated from the main part and it was put in etsubo (a pocket for ei attached to the back of the main part) to be fixed.
平安時代末期の院政期には、漆を厚く塗って形が崩れない冠となり、纓が本体から分離して纓壺に纓を差し込んで固定するようになった。