ESI Communications 60 Key Expansion Console DSS (Refurbished)Key Features: The 60 Key Expansion Console connects quickly to most current ESI desktop phones (on the IP Server 900 and ESI Communications Servers, as well as the legacy IVX X E S Classes).. The 60 Key Expansion Console is compatible with these ESI phone models (digital or IP): ESI 60 Business Phone; ESI 40 Business Phone; and 48 Key Feature Phone. Adds 60 more programmable feature keys.