The Cisco 100BASE-FX Small Form-Factor Pluggable (SFP) Fast Ethernet Interface Converter. This is a hot-swappable device that plugs into a Gigabit Ethernet SFP port on Cisco Catalyst 3750 Series, 3560 Series, and 2970 Series switches. The Cisco SFP provides full-duplex 100-Mbps connectivity between switches over multimode fiber (MMF) infrastructures.
100BASE-FX SFP Transceiver