Baubles is a small Minecraft addon and API that lets other mods use additional character inventory slots. It provides seven slots: amulet, belt, head, body, charm and two rings, accessed with the B key. Available for Forge on Minecraft 1.7.10–1.12.2, it adds very little content of its own.
Rent your own Minecraft server and install Baubles with one click from the server panel to support mods that use its accessory slots.