Cisco GLC-LH-SM SFP is long wavelength/long haul SFP transceiver working at 1300nm. GLC-LH-SM SFP is compatible to IEEE 802.3z 1000Base LX, its max working span is 10km over single mode fiber. Cisco GLC-LH-SM is able to work with both single mode and multimode fiber cables. Via MMF its max working span is 550 meters. We supply Cisco GLC-LH-SM SFP equivalent transceivers, these products meet laser safety, and they are with duplex LC ports and in standards SFP package.