Anklet of the Yin and Yang

Your unarmed strikes do additional radiant or necrotic damage (your choice) while you are wearing this anklet. This bonus is determined by the anklet's rarity.

In addition, while attuned to this item, you can use a bonus action to activate one of the following effects, which lasts until you use a bonus action to activate the opposite effect:

• Yin. You gain a bonus to all attack rolls, as determined by the anklet's rarity.
• Yang.  You gain a bonus to all saving throws, as determined by the anklet's rarity.

Notes: by a Monk