Fiamm Italian bus horn set. This type of air horn is often used by buses in Italy as a warning signal for oncoming traffic. For instance on narrow mountain roads. This type of air horn set is sometimes also used as an alternative for the regular Tour Horn.
A wiring schedule (several options) is included.
It is not plug and play, but with a little technical knowledge you'll be fine. (please note: wiring is not included)
If you are born with two left hands, you can always ask your garage to help you.
Always make sure you are aware of your local legislation and make sure you install it safely.