This is a Munhwa Stop Pen refill set, consisting of 12 black ballpoint pen refills with a 0.7mm thickness. It is a consumable item that allows you to easily replace the ink when the original pen runs out, enabling the reuse of the writing instrument. It is a finished product that cannot be customized with printing or engraving, and it is economical for use in offices or schools where there is a high volume of writing. Please check the compatible ballpoint pen model before purchasing.