There are several cage keys in The Witcher 3: Wild Hunt and are usually meant to help free person(s) in distress and so they show in the quest items tab. Once used, they typically disappear from inventory.

The Witcher 3: Wild Hunt

Associated quest

Cage key (fable)

This cage key is needed during the Blood and Wine expansion to unlock Balbina the Goose's cage. It can be looted off Redbeard's body after killing him.

Associated quest

Community content is available under CC-BY-SA unless otherwise noted.