Features: 1.Stable Transmission: This PCIe network card with 4 Gigabit Ethernet ports adopts RJ45 and supports up to 10/100/1000Mbps transmission with high stability. 2.4 Ports Network Card: This Gigabit Ethernet card combines a three speed IEEE 802.3 compatible with Media Access Controller with a three speed Ethernet transceiver, PCI Express bus controller, and embedded memory. 3.Multi Function: This RTL8111H network card supports fast transmission via CAT 5 UTP cable or CAT 3 UTP cable. With cross detection and autocorrection, polarity rectification, adaptive equalization, echoing cancellation timing recovery, error rectification and more. 4.Fast Cooling: This PCIe network adapter adopts heat sink for temperature cooling, which ensures high stability and longer service life. 5.Widely Compatible: This RJ45 network card adopts PCI Express 1.1 bus interface, suitable for any PCI Express x1, x2, x4, x8, or x16 slots. specification:Item Type: PCIe Network Card Material: Printed Circuit Board Ports: 4 Ethernet Ports Applicable Network: Ethernet Full Duplex/Half Duplex: Full Duplex Flow Control Chip: RTL8111H Transmission Rate: 10/100/1000Mbps Bus Type: PCI Express 1.1 Supported Protocols And Standards: csma/CD LED Indicator: 10/100/1000Mbp Applicable Operating Systems: For Win 10(32/64), 8/81(32/64), 7(32/64), For Vista(32/64), For XP(32/64), 2000 Ambient Operating Temperature: 0 to 70 Relative Humidity: 10% to 90% (No Condensation) Storage Temperature: Minus 10 to +80 Relative Humidity: 5% to 90%(No Condensation) Product Size: Approx. 110 x 55 x 20mm / 4.3 x 2.2 x 0.8in ( Manual Measurement, Slight Error May Exist ) PackageList:1 x PCIeNetworkCard 1 x Holder