It is a WDM module with multi ports, combines GPON/XGSPON/NGPON2 upstream and downstream signals into 1 fiber, when you update the network and using XGSPON and NG-PON2 technology, new XGSPON and NG-PON2 subscribers can share same Optical Distribution Network with existing GPON users through this WDM module, so no need deploy new fiber, PLC splitters, etc., which can save a lot of cost. Here I would like to recommend you our new solutions which allow new XGSPON and NG-PON2 subscribers to share same Optical Distribution Network with existing GPON users. We can provide different package based on different deployment requirement, please check and let us know if you have interest.