Comdial GO816 Key Service Unit (Refurbished)This traditional communications system is part of Comdial's classic line of business systems. With more than 200 standard features, Comdial's DSU telephone system provides your business with the unique combination of style and performance in a single unitized cabinet. This ensures that your system will be easy to install, easy to use and easy to maintain. DSU will exceed your small business communications needs. Includes latest release voicemail