The Eternal Moon Article was the transformation brooch that allowed Usagi Tsukino to transform into Eternal Sailor Moon. It was an upgrade to the Crisis Moon Compact, created when the eight Sailor Senshi came together and combined their powers, focused on Super Sailor Moon. Her brooch fluctuated between the Crisis Moon Compact and the Eternal Article until episode 172, where all ten Sailor Senshi along with Prince Endymion combined their power against Queen Nehellenia; from then on the change was permanent.
The colors of the gems on the brooch corresponded to the respective Senshi color themes. The gems on the left side represented the Inner Senshi, while the ones on the right side were those of the Outer Senshi, and the pink gem in the middle stood for Sailor Moon.
- In the manga, Usagi possessed a similar brooch, but she did not use it as a transformation item. Instead, she used the Holy Moon Cálice to transform into Eternal Sailor Moon.