To separate voice signal and ADSL data signal which transfer in the same phone line so as to reduce the interference to telephone or Fax when using ADSL. - Housing one input port for line - Housing two output ports one of phonethe other for ADSL modem. Telephone RJ11 Line for ADSL Modem Micro Filter Splitter Telephone RJ11 Line for ADSL Modem Micro Filter Splitter easy to use for tm streamyx more stable with two transformers high quality