The FreePBX Sangoma 60 A appliance as outlined below and FreePBX Distro. In this configuration the Appliance is recommended for up to 60 extensions and 40 concurrent calls.extensions. Specifications of the Appliance are as followed; Table Top/1U Rack Mount 2 PCI Express Full Length Slots 3 Onboard GIG Network Ports Single 120GB SSD drive Quad Core Processor 4 GB of Memory 1 Year Hardware Warranty 10.5in D X 12 3/4in W X 2.75in H Box size is 14in L X 16.6in W X 7in H and weighs 20 lbs