Baubles Mod (1.21.2, 1.21.1) is a small addon mod and api that is intended to be used by other mods to add additional inventory slots to a character. It adds 7 new slots: an amulet, belt, head, body, charm and two rings slots.
Source: Baubles Mod (1.21.2, 1.21.1)
Check Out: Minecraft Mods
Also visit : 9minecraft