The listing, RTX Phone Jack extension has ended.
This device uses your house wiring to create a telephone jack in a room that isn't wired for one. I used it to put a jack in the living room so the TIVO could dial in and get television listings from TIVO HQ, wherever that is. Most people use it just to add a phone in a bedroom or whatever.
Apparently you can add more receiver units, I only needed the one.
We don't seem to have the instructions, but it's pretty much plug-and-play. You can download instruction or watch a video about it, just Google RTX 3240.
This unit still works great, we got a fiber-optic bundle that includes a DVR so we don't need it anymore.
Free US/Canada shipping