HG660-TW is designed as HGU (Home Gateway Unit) in different FTTH solutions. The carrier-class FTTH application provides data and video service access. It is based on mature and stable, cost-effective XPON technology. It could switch automatically into EPON mode or GPON mode when access to the EPON OLT and GPON OLT. It adopts high reliability, easy management, configuration flexibility and good quality of service guarantees to meet the technical performance of EPON Standard of China Telecom CTC3.0 and GPON Standard of ITU-TG.984.X. It is designed by Realtek chipset 9607C.