Ammunition, common (twelve balls)
These balls can be shot from a sling or from any arm that takes a ball of this size. When a ball strikes anything at all it rings: one clear bell note, heard a mile over open water and half a mile over land, through walls, wool, and shut shutters. A creature struck takes the weapon's damage as normal and must succeed on a DC 12 Constitution saving throw or be deafened until the end of its next turn.
A ball is spent in the shot and is found afterwards flattened and dull, and it will not ring again. Eleven of the twelve ring. The twelfth was not finished.
Source: Provenance — The Quist Sale