It is recommended to submit the extraction study report for the product under application, clarifying the extraction method and the basis for determining the extraction limit. If the extraction study report of products of the same kind or similar products is submitted as the basis for such determination, it is recommended to select products with similar formulation, e.g., those only with differences in content of color additives. It is not recommended to select products with significant differences with the product under application in formulation. It is also recommended to describe the similarities and differences between the selected products and the product under application and demonstrate that such selected products are representative, which can be discussed from raw material formulation, dry weight of both products, recommended wearing period, etc., and analyze whether the differences affect the results of extraction study. Attention should be given to the rationality of the upper limit of extraction rate.