Connected respectively via DB-15 and RJ-45 connector, Models 4127 and 4129 convert RS-485/RS-422 serial communication interface to HP Versatile Link plastic core cable and provide full galvanic isolation between connected devices. They allow electrostatic or electromagnetic interference-free data transfer of optical fibers to be used by devices with RS-485/RS-422 interface, enabling data transfer rates greater than 20 kbps.