A family of RS-232C fiber-optic transceivers is used for serial, asynchronous, full-duplex data transfer on plastic or glass fiber cables. Data is transferred at rates to 40 kbits/sec, using Xon/Xoff protocol with transmission distances up to 1000 m when using glass fiber cables. Applications include interfacing a central location to remote facilities by using optical signals that are immune to electrical noise, ground loops, surges, and lightning transients. Operating temperature is 0 to +65C and storage temperature is -20 to +85C. A full set of accessories is available, including fibers and tools for grinding and finishing the fibers.