Jumper device for answering mobile calls using car speakers jumperjack phone dev

[Segawa]

whats the website for that Device called a jumper jack for answering mobile calls via car speakers

 

[doc969]

whats the website for that Device called a jumper jack for answering mobile calls via car speakers, and does it work?

 

[Roy81]

have a help web site for jumperjack. Its www.JumperJackHelp.com. My jumperjack just increases the the music volume on 99.3 fm when I use the radio volume control like they tell you do to increase the caller volume.That web site doesn't help solve my problem. so the jumperjack is worthless to me.