These drives are normally pronounced and referred to as "u-dot-3" drives and have been developed for high-end Enterprise environments. U.3 drives are backward compatible with U.2 but you cannot use a U.3 drive in a U.2 bay. Here at MemoryCow we stock U.3 SSDs in capacities of 15.36TB (15360GB), 12.8TB (12800GB), 7.68TB (7680GB), 6.4TB (6400GB), 3.84TB (3840GB), 3.2TB (3200GB), 1.92TB (1920GB), 1.6TB (1600GB) and 960GB and we stock U.3 drives from some of the worlds leading brands including; Micron.