The 100 Base-LX SFP Transceiver from Cisco is a hot-swappable input/output device that plugs into Fast Ethernet ports, dual-rate Fast/Gigabit Ethernet ports, or Gigabit Ethernet ports of a Cisco switch or router, linking the port with the fiber cabling network.
This Operates on ordinary single-mode fiber-optic (SMF) link spans up to 10 km long and such modules operate in Fast Ethernet or dual-rate Fast/Gigabit Ethernet ports of Cisco switches and routers.