Cisco GLC-LH-SMD 1000BASE-LX/LH SFP is made for Both Multimode and Single-Mode Fibers with SwitchTechSupply. The 1000BASE-LX/LH SFP, compatible with the IEEE 802.3z 1000BASE-LX standard, operates on standard single-mode fiber-optic link spans of up to 10 km and up to 550 m on any multimode fibers.