The car siren is not only for vehicles, but also Anywhere for its appropriate usage. It is handy but loud and clear for its size. You have to be firm and solid when on the PA speaker for volume. The tones can be heard clearly even a mile away. The car siren is also perfect for Security Vehicle-Emergency Response Vehicles (ERV). The Partol sound car siren is Easy To Install just connect the RED wire to a 12v source (inline fuse included). Run the BLACK wire to a ground (or negative battery post). With very large vehicles, the installer may need to purchase additional wiring to elongate the wires. It installs anywhere with 12V DC Power. You can install it in Car, Truck, Jeep, RV, Boat,