Add A Gigabit Ethernet Port And A Usb 3.0 Pass-Through Port To Your Laptop Through A Single Usb 3.0 PortThe Usb31000sptw Usb 3.0 To Gigabit Ethernet Adapter Lets You Add A Gigabit Network Port To Your Macbook Or Ultrabook Computer Through A Usb 3.0 Port And Features An Integrated Usb 3.0 Pass-Through Port That Keeps Your Usb Port Available For Use With Other Peripherals. The Rj45 Port Supports 10/100/1000 Mbps Ethernet And Is Fully Compatible With Ieee 802.3I/U/Ab Standards.An Ideal Replacement Lan Adapter Or Laptop Accessory This Compact Usb 3.0 Nic Leverages The 5 Gbps Speed Of Usb 3.0 To Provide Full Gigabit Bandwidth And Also Offers Backward Compatibility With Usb 2.0 Systems (Speed Limited By Usb Bus).The Adapter Supports Features Such As Ipv4/Ipv6 Packet Checksum Offload Engine (Coe) And Tcp Large Send Offload To Reduce The Load On Your Cpu. Jumbo Frames Full-Duplex Operation With 802.3X Flow Control And Vlan Tagging Are Also Supported Making This An Efficient And Full-Featured Usb Network Adapter.Backed By A Startech.Com 2-Year Warranty And Free Lifetime Technical Support.The Startech.Com Advantage- Full Gigabit Bandwidth Support Through A Usb 3.0 Host Connection- Conserve Available Usb 3.0 Ports With Usb Pass-Through- Take The Adapter Anywhere With A Portable Usb-Powered Design