Mini GBIC Transceiver,1000BaseSX (LC-Duplex) max 550m 1x 1000 Mbit Multimode Fiber SX (LC-Duplex) Port, Multimode Fiber 50/125µm tot 550m, Multimode Fiber 62.5/125µm tot 220m, Full-Duplex, 802.3x Flow-Control, Hot-Swappable.