Iromuji

A kimono that is painted in one color only and has no patterns (though, there can be a slightly visible woven pattern sometimes, but never painted, clearly visible pattern).
It's rank is lower than houmongi but if it has a mon (family crest), then the rank goes up and the can be equal.
Higher ranked iromuji is worn with fukuro obi, lower ranked can be worn with nagoya obi, too. Good for going out for formal or semi-formal occasions.