Ring of the Barbarian (5e Equipment)
From D&D Wiki
A ring passed down through generations of barbarians. The ring has been embued with the spirit of the barbarian’s anger across the ages. As a barbarian you can feel the rage and anger eminating from it and are immediatly corrupted by it upon wearing the ring.
This ring can only be used by barbarians.
The ring grants the user one additional use of rage per long rest.
The ring also grants the wearer the ability 'extra attack'.
If the wearer is using the barbarians 'unarmored defense' ability then you gain an increase in AC equal to the barbarians rage damage bonus.