- 90 Vac Ring or Dry Contact Closure Activation- Connects Directly To C.O. Line or PBX Station Lines- Provides Ringing Over Paging Speakers- Provides Contact Closure to Activate Loud Bells During Ringing- Accommodates 6 Lines Each – 4 Units can be Connected Together for UP to 24 Lines- Built-In Warble Tone Generator, Interrupter, Volume Control, and Punchdown Block