Qnap Dual-Port SFP28 25GBE Network Expansion Card (QXG-25G2SF-CX4) - Controller: Mellanox ConnectX-4 Lx, Connector: SFP28, PCIe Interface: PCIe Gen3 x8, Transmission Rates: 25Gbps/10Gbps, Supported Operating Systems: QTS; Windows (Driver required); Linux (Driver required), Supported QNAP NAS: Models with PCIe Slot(s) (1 free slot required), Bracket: Low-Profile Bracket Pre-installed, Port and cable: SFP28 DAC Cable (3M)