Sagari are the cords hanging down from the wrestler’s mawashi.
In the past, wrestlers used to fight in their kesho-mawashi, but the heavy ornamental apron hampered them, and it is also very hard to clean. So the kesho-mawashi became a purely ceremonial item, and for fighting purposes, it was simplified into the sagari cords.
Sagari are separate from the mawashi itself, hanging from a sash that is tucked into the mawashi. This is in order to prevent broken fingers should they get caught in the cords.
Low-ranking wrestlers have loose sagari. Sekitori use stiffened sagari, as straight and stiff as pencils, which match the color of the mawashi. So how is that achieved?
It is usually the duty of the Sekitori’s tsukebito to stiffen the sagari. And the pearl of the day is Itadaki of Isenoumi Heya showing us how he stiffens Nishikigi’s sagari:
— 頂 仙之助 (菊池政彦） (@hsBgR7QJL7eI1Cc) July 7, 2016
Glue is applied to each of the silk tufts, making sure (using one’s nails) that it is absorbed by every strand. The excess is removed – and the width adjusted – using a piece of cloth. The end is nicely flared, and the whole cord is stretched on the board to dry.