Build dependable 10 GbE connectivity into server platforms that need flexible fiber options. The AddOn T420-CR-AO provides dual open SFP+ ports on a PCIe x8 interface, giving infrastructure teams the bandwidth headroom required for virtualization, storage access, and high-volume east-west traffic. Open SFP+ ports let you choose the transceivers that match the deployment, whether the design calls for short-reach links inside the rack or longer fiber runs across the room. That flexibility matters when standardizing hardware across mixed server environments. The card’s dual-port layout also supports cleaner network segmentation or redundant uplinks without consuming additional expansion resources. For teams replacing lower-speed adapters, this model offers a straightforward path to 10 GbE without changing the server platform. It is a focused, server-class fiber adapter built for environments where port density, transceiver choice, and PCIe x8 compatibility all affect the final deployment.