The x4120-1048 is a 10 Gigabit Ethernet copper to fiber media converter. It offers conversion technology by providing one 10GBase-T RJ-45 port and one pluggable 10GBase-X fiber SFP+ port. The open SFP+ port supports a wide variety of Transition Networks 10GE SFP+ fiber modules, as well as third party MSA compatible SFP+ modules.

The x4120 provides several 10G Ethernet enterprise and data center connectivity solutions. Since most 10G Ethernet switches support a combination of copper RJ-45 and open SFP+ ports, the x4120 allows users to convert either of these ports to the media type of their preference to match their network requirements, including direct attached copper SFP+ cables.