I am also listing this on other flea market sites, so I will delete the listing when it's gone. Although the item has been opened, it is new and unused. The product number was written on the back of the package from the time of purchase. Size (white backing card): 6.5 x 12.5 Due to being a foreign product, there may be scratches, scuffs, air bubbles, or stains. Please refrain from purchasing if you are sensitive to these issues or if you are looking for a perfect item, as it has been stored at home. Please peel off the blue protective sheet when using. 50 yen discount on the second stamp plate and onwards! Please comment before purchasing.