Cisco 400G-FR4 QSFP-DD Transceiver, Duplex LC, 2 km Single-Mode

Duplex LC and 2 km define the Cisco QDD-400G-FR4-S. It is a QSFP-DD module at 400GbE, titled 400G-FR4, and runs on single-mode fiber.

Because the connector is a normal LC pair, it can reuse the duplex single-mode patching that most sites already have. That simplifies upgrades from slower links, as long as the distance stays within 2 km. Before ordering, check the fiber type and the length of the span, and confirm that the switch lists this module among its supported optics. If you plan to replace an existing module, send us its part number and we will cross-check the two. Ask for the far-end module in the same request so both ends arrive together and can be tested.

Both ends of the link need the same module type, and the host needs QSFP-DD cages. The FR4 here is offered in new and refurbished condition, each with a choice of 1 year or 3 years of warranty.