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futokorogatana
Translating as "chest sword", a small dagger held in a small, decorative brocade-fabric purse tucked into the collar of a woman's wedding kimono. Similar to a kaiken. (Wikipedia)
Sometimes, they can tucked in the obi instead. The purse that holds the futokorogatana is usually tied with flower knot.
Usually comes in a set with a hakoseko and a folding fan.
Examples
