Add-On's bulk packaged J4859C-AO is the perfect choice for larger qty upgrade needs. 10 piece bulk trays allow for easier configuration, over the hassels of individually packaged product. Add-On's industry-standard SFP is a hot-swappable input/output device that plugs into a Gigabit Ethernet slot, linking the port with the fiber-optic network. These transceivers (GBIC, SFP, XFP and XENPAK) are 100% compliant for all of our networking product lines. Add-On transceivers are factory loaded with OEM specific configuration data required for networking compliance. These transceivers provide a full-duplex gigabit solution up to 10 km (singlemode) or 550 m (multimode).initialize and perform identically to the OEM transceivers, and can be mixed and deployed with other OEM or 3rd party transceivers, for seamless network performance.