NVME NGFF TO SFF-8639 Expansion, PCIE 3.0 x16 GEN3. SFF-8639 U.2 High speed transmission, innovation for more beauty. 5Ax2 Two sets of high power modules, one-piece high-power inductor. Highly flexible connector, Strong connection, durable and stable earthquake resistance, Double disk can run simultaneously. B Key:m.2 NGFF of SATA protocol;usually two gaps(supported by this product),M Key:m.2 NVME of the PCIE protocol;usually a gap(supported by this product).