Properties
While holding this uncommon wondrous item, a creature has advantage on Wisdom (Perception) and Intelligence (Investigation) checks made to locate hollow spaces, concealed doors, or unseen creatures by sound. Once per dawn, the bearer can cast knock without material components. Only creatures within 30 feet hear the resulting tone.
Lore
Bellkeepers forged these palm-sized bronze instruments to test sealed procession tunnels without waking every bell beneath Embermarket. The ember crystal in the clapper resonates with worked stone and remembers the pitch of doors opened nearby.
Game Master Guidance
The bell is primarily an exploration reward. Let it reveal that a space is hollow without automatically explaining how to enter it. Its quiet version of knock avoids alerting an entire dungeon, but nearby guards can still hear it and investigate.