The white rope
The white “belt” worn by a Yokozuna is the tsuna, a large braided hemp rope. It is worn over the ceremonial apron during the Yokozuna dohyo-iri, not during a competitive bout.
The rope is the object that gives the rank its name: yokozuna means “horizontal rope.” Zigzag paper strips called shide hang from it, a form also seen at Shinto shrines. Together they mark sacred status and a purified boundary.
The Japan Sumo Association's English introduction describes the rope as weighing roughly 11 to 15 kilograms. It is made for the individual Yokozuna and tied with a large bow at the back. The shape of that bow differs between the Unryu and Shiranui styles of ring-entering ceremony.