This high quality low pass filter and is used on a line or extension where both an ADSL modem as well as a PSTN device (such as a telephone) is desired. The unit splits the line, providing a pass-through connection with no filtering to the ADSL modem, while providing a filtered connection to the PSTN device. Note that all other extensions still need to have a filter of some kind placed on them.

Digital Filter
Signals or echoes from analog devices at the top of their frequency range can result in reduced performance and connection problems with DSL service, while those from the DSL service at the bottom of its range can result in line noise and other issues for analog devices. However, this high quality low pass filter filters out these noises on the telephone line while allowing the digital signal for your DSL modem.

Line Splitter
This unit is not just a low pass filter, it is also a line splitter so it is just like getting two devices in one. And the best bit is that you don't need a seperate adaptor to split the line! And of course it comes with a short cord with the common RJ11telephon line plug on each end.