Fire-Lite ECC-50W-70V Audio Amplifier Module, 50W, 70V, Red increases the total ECC 50 100 Power output to 100 Watts Modular design for system flexibility and easy expansion Features UL Listed to UL 2572 communication (Control Units Mass Notification Systems) and UL 864 (emergency voice eV ACuation for fire) Removable terminal blocks for ease of servicing and module replacement50W of 25V audio power (expandable to 100W) RMS 2 amp Notification Appliance Circuit (NAC) output, sync generator, or follower for System Sensor, Wheelock or Gentex protocols Optional 70.7VRMS conversion transformer available for the primary amplifier. (Note that speaker wiring continues to be supervised in standby, alarm and when background music is playing with this optional transformer installed)520Hz square wave tones available, which can be uploaded to the ECC-50/100 to meet NFPA Low Frequency requirements