This is an Astro Boy (Tetsuwan Atomu) clear file. It says "Special Handling Approval Magazine No. 276, March 28, Showa 24 (1949), Japan National Railways." It's likely a clear file based on the design of that magazine. Also, it says "Shonen Shinsho New Year's Issue Supplement" in the lower left corner. It is not unused. Please refrain from purchasing if you are a perfectionist or overly concerned, as it has been stored at home. Only those who understand are welcome to purchase.