The bottom of the utensils is polished beforehand at our store to prevent scratches on tables, etc. If you are concerned about the roughness, please polish it a little with sandpaper before use.
When using, please soak the container in water once. By passing it through water, it prevents odors and dirt. (If you are particularly concerned about dirt, please fill it with water and let it absorb enough water until no air bubbles appear.)
When wet, a gray stain may appear, but don't worry, it will disappear once it dries.