10Gtek for Cisco GLC-EX-SMD, Gigabit SFP EX Transceiver, 1000Base-EX, SMF, 1310nm, 40km Compatible for Cisco GLC-EX-SMD 1000BASE-EX SFP transceiver module for SMF, 1310-nm wavelength, dual LC connector 1G SFP Transceiver, SFP EX, 1000Base-EX SFP, 40km 100% Compatible with Cisco.10Gtek owns Compatibility LAB to meet the coding requirements for various brands of switches and routers. Each transceiver is individually tested on Cisco switches and we will make sure 100% compatible before delivery 10Gtek offer more compatible options, if your brands not listed above, pls contact us