3CX VOIP Phone System is an Office Phone System/IP PBX that completely replaces a proprietary PABX, supports standard SIP soft/hard phones from any vendor, VOIP service providers & traditional PSTN phone lines. Developed for Windows, it is easy to install, configure and manage via Web-based config. Eliminates phone wiring, allows hotdesking & roaming, saves on call costs and includes auto attendant.