FC-to-SC FDDI adapters allow newer versions of the Cisco 4000 series FDDI network processor module, and the FDDI Interface Processor (FIP), to be connected to existing FC-type optical fiber. All newer FDDI products are equipped with SC-type connectors and replace older versions of these products equipped with FC-type connectors; this FC-to-SC adapter prevents you from having to change the existing connectors on your FC-type fiber-optic cables. (You can also reverse the FC-to-SC adapter and use older FC-type, single-mode FDDI products with SC-type, single-mode optical fiber.)