Only tried on indoors. Kenko Misato-cchi are designed to make you use your toes with every step. It is said that using your toes helps children develop arches in their feet and promotes brain development. For adults, it can improve bunions and activate the brain. For the elderly, it can be expected to keep the brain youthful. Ingredients: Tatami surface: Natural Igusa from Kyushu Sole: 40% natural rubber + 60% synthetic rubber Tatami surface edge: Olefin resin (environmentally friendly specification that does not contain vinyl chloride)