The quality Valcom V-2924A Expandable Paging/Intercom Controller (24 Ports). 

FEATURES

• 24 one way paging and/or two-way intercom circuits
• 4 Separate Paging/Tone groups per unit
• Background music and tones are group selectable
• Standard twisted pair CAT 2-6 system connections and blocks
• Caller ID loop start trunk C.O. Line position PBX interface
• 4 auxiliary relays for controlling door locking/unlocking access
• SMDR printer output provides record of system activity
• Built in connector for optional battery backup operation (VPB-260)
• Multiple V-2924A units may be interconnected for global all call
• UL and FCC Listed , Registered or Approved

This product comes with a standard Manufacturer Limited Warranty