I read in a thread about the backup siren/alarm and battery to serve as your 2nd siren in case carnappers cut off the main alarm.

Ang tanong ko is do you guys know a place/shop na nagiinstall nito? My car only has the factory alarm with it (TVSS) and gusto ko palagyan ng both main alarm and backup alarms ( piezo siren para maliit at nakatago sa ilalim ng dashboard). Kung sa banawe, sino sa kanila magaling maginstall?

May particular brand ba ng alarm system na add-on ang backup siren, or any brand will do? TIA