Ubiquiti's UACC-SM1GS is ideal for long-distance, bi-directional, single-mode connections. It can deliver up to 1.25Gbps speeds at distances of up to 3km. These SFP modules make use of Wavelength-Division Multiplexing (WDM). This means it uses two different light wavelengths to transmit data in both directions at once, resulting in fewer fibre cables required to run. It also aids in maximising the use of existing infrastructure and simplifying installations. *Note: The price reflected is for a pair (one box of 2 units). This product is only sold as a pair and no single units are available.