Ratoc Systems, Media Converter, models:

FR1SX	User Manual
RAL-DSDHA2	Setup Manual
RAL-KEB02iP	User Manual
REX-USB61	User Manual
U2SCX-LVD	User Manual
U2SCXU	User Manual
USB-Serial Converter REX-USB60	(Japanese) Product Manual Product Manual
USB-Serial Converter REX-USB60F	Installation Manual (Japanese) Product Manual