Adds Expansion Card Slots to Any Computer with a Thunderbolt Port-The standard Echo Express supports one half-length (up to 7.75"), full-height, double-width, x16 (x4 mode) PCIe 2.0 card; the Echo Express Pro supports two standard width, full-length cards, or one double-width, full-length card * High Bandwidth-x4 mode 1GB/s PCIe 2.0 slot(s) perfect for special-purpose PCIe cards for video capture, audio interface, 8Gb Fibre Channel, 10 Gigabit Ethernet, digital audio, RAID control, and more * Power for Powerful Cards-Integrated 100W power supply (150W in Pro model) * Two Thunderbolt Ports-Daisy chain up to six devices to a single port on the host computer * Variable Speed Fans-Operate slow and quiet with cooler cards, better cooling for hot cards