In Brazil, bottled liquefied petroleum gas is a common household fuel, and delivery trucks have long announced their arrival with music played from loudspeakers as they pass through residential streets. Different companies and regions use different melodies, which is why the sound is tied less to one song than to the daily ritual of listening for the truck, signaling the driver and swapping an empty bottle for a full one. Recordings of the announcement later spread through WhatsApp groups and short videos, where the familiar loop became shorthand for Brazilian neighborhood life and nostalgic humor.