◇ If the sponge gets dirty, the surface of the foundation will harden and it will be difficult for it to stick to your skin, so always keep it clean. ◇When the sponge becomes dirty, use the separately sold "Shiseido Sponge Cleaner N" or wash it by lightly pressing it with a mild detergent diluted with lukewarm water. After rinsing thoroughly so that no detergent remains, drain the water and dry well in the shade before using. ◇If the case cannot be opened and closed smoothly, please purchase a new case.