PLANET GT-1205A Gigabit SFP Media Converter is upgraded by providing dual SFP slots; accept 100FX or 1000X SFP module, and other features shown below:  DIP Switch for 100FX or 1000X SFP module supports on dual SFP slots DIP Switch for 3-port Operation in Gigabit Switch Mode or Redundant Mode Redundant Hardware Fiber Port  Highly Convenient and Distance Extendable The GT-1205A is equipped with one 10/100/1000BASE-T port and dual SFP slots to support conversion between 10/100/1000BASE-T and 100/1000BASE-X network. The dual SFP slots make the Ethernet signals connect easily and efficiently by adding single-mode or multi-mode media modules or the combination of both types. The GT-1205A provides high reliability and flexibility to extend the media transmission distance up to 550m or 2km (multi-mode fiber) and 10km or longer 20/40/80/120 kilometers (single-mode fiber or WDM fiber), depending on the optional 100/1000BASE-SX/LX SFP modules. Adjustable DIP Switch for 100FX or 1000X SFP Module Selection Via the built-in DIP switch on rear panel, the GT-1205A can be configured as supports 100BASE-FX SFP module or 1000BASE-X SFP module on its dual SFP slots, the GT-1205A can be connected over fiber optic cabling at a distance extended from 550 meters to 2km (multi-mode fiber) to 10/20/40/80/120 kilometers (single-mode fiber or WDM fiber), using the PLANET MFB/MGB series 100/1000BASE-X SFP modules. Adjustable 3-Port Switch Mode or 2 Fiber Port Redundant Mode Via the built-in DIP switch, the GT-1205A can be configured as 3-port Ethernet switch or 2-port redundant media converter. In the 3-port switch mode, the GT-1205A can operate in Store-and-Forward mechanism with high performance; on the other hand, when in the 2-port redundant mode, it provides rapid fiber redundancy of link for highly critical Ethernet applications. The redundant mode also supports auto-recovering function. If the destination port of a packet is link-down, it will forward the packet to the other port of the backup pair. Easy Deployment Standalone or with Chassis  The GT-1205A Gigabit Media Converter can be used as a standalone unit or as a slide-in module to the PLANET Media Converter Chassis, MC-700 and MC-1500 chassis series. These media chassis can assist in providing DC power to the GT-1205A Gigabit Media Converter and the fiber-optic network can be maintained at one central location. With the 3-port switch mode, they work in high performance Store and Forward mechanism, and prevent packet loss with IEEE 802.3x Flow Control (Full-duplex) and Back Pressure (Half-duplex) function.   Plug & Play Installation  As the GT-1205A Gigabit Media Converter fully complies with IEEE 802.3 10BASE-T, IEEE 802.3u 100BASE-TX/FX, IEEE 802.3ab 1000BASE-T and IEEE 802.3z 1000BASE-LX/SX, the Gigabit media conversion installation is quite quick and easy simply by using the plug and play feature.