Cisco Expansion Module – For Data Networking, Optical get more info Network – 4 x 1000Base-X Network – Optical FiberGigabit Ethernet – 1000Base-X – 1 Gbit/s – Plug-in Module – 1 Pack Features With 1000Base-X technology, get up to 1000Mbps data transfer rate over supported network cable Gigabit Ethernet port for ultra-fast network