Use only the SFP modules with your Modular Gigabit Ethernet line card. The Cisco 100BASE-FX Small Form-Factor Pluggable (SFP) Fast Ethernet Interface Converter (GLC-GE-100FX=) is a hot-swappable device that plugs into a Gigabit Ethernet SFP port on Cisco Catalyst 3750 Series, 3560 Series, and 2970 Series switches.
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