The Pandora DS-530 is a single-tone non-autonomous 20 W siren with 117 decibel volume pressure, current rating 1000 mA, 12V operating voltage. It is waterproof and has 9-15 V positive-going and negative-going signal outputs.
The Siren switches on after any of the alarm's sensors has been triggered – if there is the warning level, the siren will produce several short signals, while the alarm level will trigger the full howling.