Mitsuuroko is a kind of Japanese family crest "scale". It is a design that stacks three equilateral triangles into pyramid shapes. Japanese clans Ogata clan, Hojo clan, etc. used it. In particular, Mr. Hojo used the crest of the same design, but he also uses three scales composed of a long isosceles triangle at the bottom, which is called "Hojo Rin".
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Mukai