Tsuba, Japanese sword guard

The sword guard, called tsuba in Japanese, has a double role, to protect the hands and to perfect the balance the sword. Over time, tsuba have been made in many shapes, one of the most popular being the four lobed shape (mokko gata in Japanese), like the one photographed here.

The middle opening was, of course, mandatory because that's where the sword's tang fits, but the lateral holes were optional, the left one was made to allow a small utility knife mounted on the sheath, while the right one was for a hair arranging tool called kogai.