Provides four channels of optical-input-to-optical-output functionality. Supports four standard MSA SFP optical transceiver (Tx/Rx) modules, purchased separately. The M440 has been tested for correct operation with 3G SDI video signals. (It's possible that it will also function correctly with 6G and 12G SDI video signals.) Powered by 5 to 17 volts DC. Uses a 4-pin MTA100 "header" connector for access to power entry and future RS-485 data. Uses a 5-pin MTA100 "header" connector for access to status LED outputs. This is a circuit board assembly that requires a mounting enclosure, interface cables, and external source of power. For use in specialized applications that are designed and implemented by technically-proficient personnel.