Sonnet Echo Express SEL Thunderbolt 2-to-PCIe Expansion Chasis (ECHO-EXP-SEL) Use high-performance PCIe cards with any Mac with a Thunderbolt port Maximum performance with computers with Thunderbolt 2 technology, backward compatible with host computers and other devices equipped with 10Gbps Thunderbolt technology Daisy chain up to six devices to a single port on the host computer Most compact Thunderbolt 2-to-PCIe expansion system available, designed to fit the most popular Thunderbolt-compatible high-speed networking and storage controller interface cards Includes Thunderbolt cable and ThunderLok Thunderbolt connector retainer clip to secure cable from accidental disconnections