Avaya IP Office Avaya IP Office AVAYA IP500 V2 Control Unit and Base Cards (12) Avaya IP Office 500 V1 Control unit and Base Cards (8) Avaya IP400 and IP500 External Expansion Modules (12) Avaya IP400 Items (7) Digital Telephones (1400, 2400, 4400, 5400, 6400 & 9500) (24) Avaya IP Telephones (1600, 4600, 5600, & 9600 Series) (15)