A well-kept secret of Japanese skincare is now revealed Deitanseki Soap, a full-sized (5.3 oz) and black-colored (of charcoal powder) soap bar from Japan. The best selling charcoal soap bar at public bath houses (sentoh) and hot springs (onsen), now available in North America. This soap has three active ingredients working together to deliver the freshest clean. Carbon Powder draws impurities away while Kaolin Clay cleanses skin gently and stimulates circulation in capillary vessels. Then, Bentonite helps your skin retains its natural moisture.