The handle of the toothbrush is made of a material that is a blend of polylactic acid resin and fine bamboo powder, which burns fewer calories when incinerated after use, and emits less CO2 than ordinary resin. In addition, it is a sustainable toothbrush because it uses plant materials that grow in one year. The bamboo grown in Iga City, Mie Prefecture is managed in-house, and all of it is carefully made at a factory in Japan. In addition, due to the characteristics of natural materials, the handle part decomposes and loses strength, so we have set an industry-first quality retention period of 2 years. In addition, the packaging uses "bamboo paper" made from 100% Japan bamboo. [About ultra-fine hair] It is a material that has excellent suppleness, elasticity, and durability, and has a high cleaning effect. Since it is a familiar and familiar material, it can easily fit between teeth and periodontal pockets, giving it a refreshing and clean feeling.