Got a Thunderbolt or Thunderbolt 2-equipped Mac? The Sonnet Technologies Echo Express SEL Thunderbolt Expansion Chassis is ready to take it to the next level. It lets you use PCIe-based devices, like pro-level audio interfaces, with any Thunderbolt-equipped Mac. That means you can turn your laptop into a portable recording rig with a high track count, low latency, and exceptional stability. The Echo Express SEL supports one 6.6 inches (16.76 cm) long card with a low-profile PCIe card bracket attached, and has dual Thunderbolt ports for daisy-chaining your other devices. When you need maximum bandwidth, speed, and performance, add the Sonnet Technologies Echo Express SEL to your Mac.