Check the listing for details. NEC SL2100 Digital / Analog Station Card for Telephone System Expansion Module. Condition: New. Listed at 129.95 USD. Provides interface for (8) digital stations and (2) analog stations Also provides interface for: Music-on-Hold or Background Music source External paging Zone Equipped with (4) 8-conductor interface jacks. (2) for (8) digital stations (1) for (2) analog stations (or Doorboxes) (1) for Music-on-Hold/Background Music input, and External Paging Zone output, and (2) relay circuit connections. The above relay circuits are available for: Door-strike control, when analog ports are used for Doorboxes Control for Music-on-Hold or Background Music source Control of External Paging Equipment Installs only in universal slots 1-3 of Main or Expansion Chassis. Allows addition of (1) 3-Port CO Trunk Daughter Board (3COIDB) or (1) PRI Daughter Board (1PRDB). Maximum (3) per Main or Expansion Chassis. Maximum (9) per system.