This is a special braiding technique used for wrapping the box for tea ceremony goods.
Originally, they were used for the handle of the sword of the Samurai. Even Ninjas used it! So they are pretty strong and durable.
The braid is like “Kamon”(family emblem). This family emblem was used so that we could recognize who you are; nowadays this tradition is still kept in the tea ceremony. Each tea school has its own braid.
You can buy Sanada braid: