The LevelOne SFP-9221 is a powerful and cost-effective SFP transceiver. It provides up to 1.25Gbps bi-directional data transmission up to 10km on a single optical fiber core. The bi-directional SFP transceiver can transmit through a single optical fiber data in both directions, using different wavelengths are used for both directions. The SFP-9221 transceiver transmits with a wavelength of 1310nm and 1550nm offers having a wavelength of. If a LevelOne SFP-9221 transceiver is used, you will receive bidirectional data communication (1310nm TX and 1550nm RX) via a single optical fiber core.