Whelen Howler Low Frequency Vehicle Speaker BottomCondition: * New stock, no OEM packaging.* Speaker only, no mounting hardware.* As pictured.Additional Notes:* Add-on to any 100/200-watt siren amplifier (not included)* Uses low frequency tones to synchronize with the vehicles primary siren tones* Works with any sweeping, Hi/Low, or electronic mechanical tones generated by the primary siren* Tone Durations: 8 durations, 7.5-60 seconds* Scan-Lock allows for easy set-up of tone duration and frequency style* Uses the primary siren speaker output wires and divides the frequency to one of three frequency bands via Scan-Lock buttons Selections are tone, tone, or a composite of both* Includes two external cancel controls: choose from 12 volt or ground deactivation* Certain vehicle models may utilize single or dual speaker systems