Promise Pegasus R4 is the first four-bay high-performance hardware RAID solutions designed to unleash the raw power of Thunderbolt. Pegasus R4 features four 1 TB 7200-rpm hard drives in a compact hardware RAID enclosure with Thunderbolt connectivity. Delivering over 500 Mbps of disk performance, Pegasus is compatible with Mac systems with Thunderbolt & required Thunderbolt cable. Thunderbolt technology is a high-speed, dual-protocol I/O technology designed for performance, simplicity, & flexibility. Capable of delivering a blistering two channels of bi-directional 10 Gbps per port of performance, Thunderbolt technology combines PCI Express & Display port into an interface using a single cable for connectivity to devices. Thunderbolt technology was developed by Intel & brought to market with technical collaboration from Apple. Pegasus R4 is ideal for creative pro workstations, small servers, power users, & consumers who desire stylish high-capacity external storage with high performance & enterprise level data protection. Pegasus R4 is capable of delivering over 500 Mbps of bandwidth that is 10 times faster than USB (Universal Serial Bus) 2.0.