Some retailers that offer Thunderbolt drive enclosures include Amazon.com and MacSales.com. As of December 2015, Amazon.com offers the Akitio Thunder2 Quad and OWC Mercury Elite Pro Dual thunderbolt enclosures. The Akitio Thunder2 Quad enclosure supports both a 2.5-inch solid-state drive and a 3.5-inch hard disk drive.
The OWC Mercury Elite Pro Dual thunderbolt enclosure available on Amazon.com supports up to two 3.5-inch SATA hard drives and is compatible with both Mac and PC. MacSales.com offers the OWC ThunderBay 4, which is a professional grade Thunderbolt drive enclosure that supports up to four 3.5-inch drives including SSD and HDD. This enclosure is RAID-ready and is compatible with both Mac and PC.