Cisco MGBSX1 Gigabit Ethernet 1000BASE-SX SFP Transceiver for Multi-Mode Fibre, 850 nm wavelength, supporting distances up to 500 metresCisco MFE & MGE Small Form Factor Pluggable (SFP) or mini Gigabit Interface Converter (mini GBIC) transceivers are easy to install modules that provide a simple way to add fiber connectivity or to add an extra Gigabit Ethernet port to your Cisco Small Business or Cisco Small Business Pro Series switches. The transceivers are available for single mode or multimode fiber optic cabling and can support distances from 100 meters up to 40 kilometers.