The Grandstream UCM6308A is a high-end, 1U rack-mountable Audio IP PBX designed for small-to-medium businesses, supporting up to 1500 users, 200 concurrent calls, and 150 concurrent SRTP calls. It features 8 FXO (trunk) and 8 FXS (telephone) ports with lifeline capability, 3 Gigabit network ports (PoE+), USB 3.0, and an SD card slot for storage
