Gives you ability to connect from a single jack that carries two phone numbers to break-out Line1 and Line 2. It also "gives" you back the original combined single jack with line 1 & 2 on it. You may also utilize this little guy on a single line jack to plug just two devices in and share a line. Pretty versatile piece You get all ten pieces shown here. About $6.95 each and more at the "Shack" or "Good Guys" type outlets. Now in a modern White color! Warranty: One Year by www.wiredco.com

QUESTION:
I have a single jack in my home office with two phone numbers on it, can I somehow connect my computer on line one and my telephone on line two?

ANSWER:
You will need a splitter, not just a regular line splitter, but one that will take line-1 to the line-1 position in one slot and then take line-2 to the line-2 position in the second slot. My splitter here have a third slot that offers both line-1 and line-2. Radio Shack's item number 279-432 costs about $6.95 and up, we have it here in Wired's store for MUCH less.......

An online price I found here:
2-Line, 3-Way Jack
$8.59 ea. Brand: RadioShack