An important part of the Future Arc, the Rings allow people to bring out their resolve and use it to power Box Weapons. The ranking for the Rings range from E-rank (weakest) to A-rank (strongest), with the Vongola Rings, Mare Rings and the Arcobaleno Pacifiers being exceptionally powerful, ranked as S-rank.
The ranks of the Rings establish and imply several things. The most notable is the output of the Rings: Since Rings cannot create Flames, only release them, weaker ranks cannot release as much of a Flame output as a higher ranked Ring can. Furthermore, other things such as purity of the Flame and effectiveness of the Flame in terms of activating Box Weapons are also determined by rank.
