AddOn Network Upgrades ADD-GMC-MMSM-2SC is a Media Converter that converts a 1000Base-SX“SC” to 1000Base-LX“SC”, providing the conversion from 850nm multi-mode fiber “MMF” to 1310nm single-mode fiber “SMF”. This conversion also extends distance reach from 550m to 20km. AddOn Network Upgrade Media Converters and Network Interface Cards are 100% compliant for all of AddOn networking needs. Now you have a cost effective solution to your network upgrade needs. With the addon certification text Program, AddOn can guarantee your product will work right the first time.