Specification: * Scalable and flexible IP PBX system for growing businesses * Supports up to 1000 extensions and 500 concurrent calls * Built-in Voicemail, Auto Attendant, and Call Center features * Integrated with popular CRM and ERP systems for seamless workflow * Supports both SIP and ISDN protocols for easy deployment The Grandstream UCM IP PBX Series is a high-performance VoIP solution designed for businesses of all sizes. With a scalable and flexible architecture, this system can support up to 1000 extensions and 500 concurrent calls, making it an ideal choice for growing businesses. The system also features built-in Voicemail, Auto Attendant, and Call Center capabilities, as well as integration with popular CRM and ERP systems for seamless workflow. Additionally, the UCM IP PBX Series supports both SIP and ISDN protocols for easy deployment and compatibility with a wide range of devices.