Cisco WS-G5484-RF 1000Mbit/s 850nm Multi-mode Stainless steel network media converter

1000BASE-SX Short Wavelength GBIC (MM), Refurbished The industry-standard Cisco® Gigabit Interface Converter (GBIC) is a hot-swappable input/output device that plugs into a Gigabit Ethernet port or slot, linking the port with the network. Cisco GBICs can be interchanged on a wide variety of Cisco products and can be intermixed in combinations of 1000BASE-T, 1000BASE-SX, 1000BASE-LX/LH, 1000BASE-ZX, 1000BASE-CWDM, or 1000BASE-DWDM interfaces on a port-by-port basis.

Cisco 1000BASE-SX GBIC.
The Cisco 1000BASE-SX GBIC (WS-G5484) operates on legacy multimode fiber (MMF) optic link spans up to 1815 feet (550 m) and on laser-optimized multimode fiber (OM3) optic link spans up to 3281 feet (1 km).