4 Line VoIP Small Business Telephone System. Replaces Basic Multi-Line Telephones with the X-44 Next Generation (4) Line VoIP Telephone - Provides Complete Small Business Telephone System. Features including Voice Mail System and Auto Attendant. System Capacity of (4) VoIP Telephone Lines & (16) X-44 VoIP Telephones. XBLUE WiFi Adapter Provides Complete Wireless X-44 Telephone Installation and Operation