The MC111CS is a media converter designed to convert 100BASE-FX fiber to 10/100Base-TX copper media or vice versa. Adopting WDM technology, MC111CS takes only one fiber cable to transmit and receive data, which will half cable cost for you. Designed with IEEE 802.3u 100Base-TX and 100Base-FX standards, the MC111CS is designed for use with single-mode fiber cable utilizing the SC-Type connector. The MC111CS supports longwave (LX) laser specification at a full wire speed forwarding rate. It works at 1550nm on transferring data and at 1310nm on receiving data. So the other end device to cooperate with the MC111CS should work at 1310nm on transferring data and at 1550nm on receiving data. Another TP-LINK´s media converter MC112CS is just one of the examples to cooperate with MC111CS. Auto MDI/MDI-X for TX port, Auto negotiation of duplex mode on TX port, and front panel status LEDs. The MC111CS will transmit at extended fiber optic distances utilizing single-mode fiber up to 20 kilometers(12.5 miles).