The habaki is the piece of metal circling the base of the blade. It has two main purposes: locking the tsuba in its place and holding the sword into the Saya.
Unlike the Shinken Habaki which can be very expensive, the Iaito Habaki are standardized and gently forced into place. This means removing or changing the Habaki on an Iaito blade is not recommended.
Habaki are made of brass and are available in three different designs: Muji, Shonai, and Yujo, and in 3 different finishes: black (oxidized), and silver plated. Please note that due to the oxidation process, it is not possible to blacken the Shonai design.

The Seppa are washers used in front and behind the tsuba to tighten the fittings, made of copper or brass. They are compulsory to keep the Tsuba safely in place.
They are available in brass, copper, black (oxidized), and silver-plated brass.