Keyring

A keyring is a miscellaneous item in Fallout 3, Fallout: New Vegas and Fallout 76.

Gameplay
It appears in the Pip-Boy inventory under the "Misc" heading. Selecting it allows the player character to see all of the individual keys they have found, received, and stolen. This includes physical keys, key cards, access codes, VIP cards, and recorded audio passwords, any item that the player character uses to access a locked door or container.