1U Plug-in Chassis https://www.wdmlight.com/1U-Plug-in-Chassis.html The 1U plug-in CWDM products are modular in design. Each CWDM card supports up to 18-wave CWDM multiplex/demultiplex. The CWDM card can be flexibly configured according to network requirements, which greatly saves customers\\\' fiber resources. The 1U chassis can provide 2/4 slots to support all types of CWDM cards. It is suitable for CWDM centralized deployment and is widely used in metropolitan area networks. 1U Plug-in Chassis Features Low insertion loss High channel isolation High stability and reliability Lightpath without glue process 2~18 channels are optional