The latest ultra-light notebooks, compact form factor, and all-in-one desktops are a small marvel of technology. However, slimness comes at a cost - PCIe cards that offer additional connectivity and processing capabilities beyond a computer's standard ports cannot be installed. Compact Mac and Windows computers with Thunderbolt 3 ports still provide enormous computing power, but for many, such as professionals in the creative field, the onboard processing power alone is not sufficient. Fortunately, one does not have to limit their options to desktop workstations. With Sonnet's Echo Express SEL (Thunderbolt 3 Edition), you can connect a single low-profile PCIe card outside the computer. Through its x8 PCIe 3.0 slot, this small expansion system supports many Thunderbolt-compatible 16 Gb and 8 Gb Fibre Channel, 40 Gb and 10 Gigabit Ethernet, video capture and processing cards, SAS and SATA host adapters, as well as RAID controller cards. The Echo Express SEL (Thunderbolt 3 Edition) features 40 Gbps Thunderbolt 3, which offers double the speed and connectivity of Thunderbolt 2 and enables PCIe bandwidth of up to 2750 MB/s, allowing it to support 4K video capture and processing cards at high frame rates, as well as 16 Gb FC cards and 10 Gb dual-port cards at full performance. With the ability to handle the most demanding high-performance PCIe cards, support for connecting two 4K displays at 60 Hz or one 5K display at 60 Hz, and compatibility with a variety of Thunderbolt and USB peripherals, Thunderbolt 3 is a significant leap forward in every way.