The readers, storage drives, & hubs leverage USB (Universal Serial Bus) 3.0 technology for high-speed performance, while the Professional Workflow HR2 hub & CR2 CFast 2.0 reader are also designed to deliver next-generation Thunderbolt 2 speeds. Thunderbolt 2 technology gives photographers & videographers the power to quickly transfer 4K video & other large media files, at up to twice the speed of Thunderbolt & up to 4x the speed of USB (Universal Serial Bus) 3.0 devices.