One end of the 1310nm FP TX 1550nm RX SC BOSA is a DFB or FP laser, which is used to transmit signals. The other end is an InGaAs detector, which is used to receive signals. The packaging is a receptacle package, which makes this BOSA ideal for use in SONET, SDH, ATM and other fields. The laser can be used in different chips and connectors based on customer requirements.