Hello & Welcome to Just Answer,
Sorry I didn't see your question earlier and to hear of any issue you are having with your device connections.
What you will actually need is the "cradle" for this series of devices (700 series), where the GTM 20 connects, and then the device "mounts" on the cradle.
I have a link to Amazon where that exact cradle & suction cup mount are listed.
Click Here --> http://amzn.to/1J8pU9y
Note: These cradle & mounts are becoming scarce, but you may be able to find only at a well stocked store - that carries a LOT of Garmin devices and accessories.
I hope this helps. Please let me know if you have any more questions.
If this has answered your question(s), please take a moment to rate MY service level (Excellent is my goal) so that I get credit for helping you with this question.You should see some "stars" to do that, but please let me know if you do NOT see them (you may have to scroll UP or DOWN) or can not use them.
Thanks, ***** *****--. .-
I see it has been a few days and I just wanted to follow up to see if you have any more questions concerning this issue or if the issue was resolved?
I look forward to any further questions or results that you may have.
Thanks, ***** *****--. .-(im)
Were you able to connect the receiver to the mount and then the device to the mount - and get it to work for you?
OK - very good.
Just so you know, any "traffic features" of the device itself will ONLY appear when the traffic receiver is connected and operating.
That is, if the device is operated on battery power ONLY, the traffic features will not be accessible on the device.
Please let me know if you have any more questions.