Beautiful 9" Round Bell Horn Speaker & Driver, New in box. Marked Motorola TDN number on box, but enclosed spec sheet shows Atlas/Soundolier HPR-370C 100W(conservative rating for electronic siren use) 180W Equalized Power for voice reproduction use) 375 - 8,000Hz Dispersion 100-degrees. 131dBA 4-feet on axis. Heavy Duty Steel Bracket, all Grey.HP370 Series. High-performance electronic siren loudspeaker provide penetrating tone signaling and high-intelligibility voice communications to enhance the functional and operational range of mobile and stationary emergency communication systems. All siren models include the world-recognized SD Series 11-ohm compression driver with double re-entrant loudspeaker for use in ambulance and emergency vehicle applications, security alarm, protective communications, community warning and 2-way radio systems. Assemblies include a 100-watt compression driver and round loudspeaker bell. Product series suitable for use with matched amplifier and control equipment in systems requiring AMECA� (for- merly AAMVA) Certification to General Services Admin. specifications (KKK-A-1822C).