The OCM 1891 is a compact CWDM passive 9 channel optical multiplexer / demultiplexer designed to send or receive up to 9 individual signals over a single fiber link. The module has an UPG (Upgrade) port to connect to the OCM 1892, which expands the capability of the modules to 18 CWDM channels.  
 
The modules can be used standalone or integrated into the optional RFR 1018 1/2 RU 19” rack frame, ideal for system installations.  
 
Ideally suited for use with the CWDM yellobrik fiber modules (all 18 wavelengths available).