I’m not sure what to make of this. After examining the Japanese text, I am still puzzled by the usage. It is probably a safety key/pin (?) relating to old Japanese airplanes. Another wild guess would be a tag for some device.
This is my place for some quiet hours. A place where I can play. To be a kid - to explore, to run around and bump into things. To see things again, as if for the very first time.