Planet GSW-1600HP User Manual page 17

 MGB-LA10 SFP-Port 1000BASE-LX (WDM,TX:1310nm) - 10km
 MGB-LB10 SFP-Port 1000BASE-LX (WDM,TX:1550nm) - 10km
 MGB-LA20 SFP-Port 1000BASE-LX (WDM,TX:1310nm) - 20km
 MGB-LB20 SFP-Port 1000BASE-LX (WDM,TX:1550nm) - 20km
 MGB-LA40 SFP-Port 1000BASE-LX (WDM,TX:1310nm) - 40km
 MGB-LB40 SFP-Port 1000BASE-LX (WDM,TX:1550nm) - 40km
It is recommended to use PLANET SFP on the GSW-2620HP. If you
insert an SFP transceiver that is not supported, the GSW-2620HP
will not recognize it.
Note
1. Before we connect the GSW-2620HP to the other network device, we have to
make sure both sides of the SFP transceivers are with the same media type, for
example, 1000BASE-SX to 1000BASE-SX; 1000BASE-LX to 1000BASE-LX.
2. Check whether the fiber-optic cable type matches with the SFP transceiver
requirement.
 To connect to 1000BASE-SX SFP transceiver, please use the multi-mode fiber
cable with one side being the male duplex LC connector type.
 To connect to 1000BASE-LX SFP transceiver, please use the single-mode fiber
cable with one side being the male duplex LC connector type.
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