Product Description

1 -- The GTM 20 is an integrated FM TMC (Traffic Message Channel) traffic receiver, antenna and cigarette lighter adapter. Designed exclusively for the American version of certain products, it receives digital information (where available) on traffic and road construction tie-ups that your compatible Garmin unit uses to offer an alternate route. TMC data, available in a fast-growing number of cities throughout North America and Europe, gives prompt, accurate notification of accidents, road construction, police, or emergency action, etc. so you can visually monitor traffic flow and, if necessary, avoid traffic tie-ups.2.Receive Real-time Traffic Data -- In most areas, depending on the service provider, TMC traffic broadcasts are continuous theres no waiting for scheduled traffic news updates or random alerts. With the GTM 20, you see traffic developments in real-time, as they happen, so you can make the right decision sooner. The system alerts you when a traffic problem is on your route and proposes an alternate route to avoid the incident. Because traffic broadcasts are received via a silent FM data channel, you can still listen to music or news programming on your car radio without interference from incoming FM traffic data transmissions.The GTM 20 is a portable, all-in-one antenna, traffic receiver, and 12-volt cigarette adapter that does not require professional installation.

Product Details

• Brand: Garmin
• Model: 010-00544-01
• Dimensions: 3.19" h x 2.24" w x .67" l, .66 pounds

Features

• Product Type - GPS Accessories
• Plug-and-play no installation required
• Provides real-time traffic information to compatible Garmin GPS car navigators
• Helps users avoid traffic tie-ups
• Graphical map symbol reference

Customer Reviews

Handy accessory, but could be better
I purchased this for my Nuvi 650. My husband and I do not commute to work during rush hour, but we do tend to drive to visit my parents' around the evening rush hour. We figured it would be handy to help us avoid the Long Island traffic that turns our 25 minute drive into an hour drive around that time. We have several different main road options to choose from, and we were hoping it would automatically route us to the ones that had no traffic tie-ups. Here's how it really works:
It continues to route you the normal fastest way, regardless of traffic. Once you get near the road where there is a traffic jam, a small yellow icon appears on the bottom right hand corner of the GPS, with a number inside it. That number is the amount of minutes you can expect to be sitting in traffic on the road ahead. Touch on the icon and it will show you the stretch of road that has the delay and it will give you an option to "Avoid traffic?". ONLY if you click yes, it will route you to a different road to avoid the traffic. (After you click yes, it will ask you something like "are you sure you want to avoid, this route is already the fastest", but click yes again. That route is the fastest WITHOUT traffic, but not with. You can tell this by the new arrival time you are given when you ask for the reroute. It's usually earlier.)
Overall, I like the receiver, it does what I need it to do, only with a few extra steps. Ideally of course, it would ask you right off the bat when you program your route if you want to avoid all traffic, because that small yellow icon can be easy to miss if you're driving alone in the car and not continually glancing over at the GPS. They should play a little sound or something when it pops up! Then it's kind of dangerous to be poking around on the unit while it asks you twice about the reroute while you should be driving! I definitely don't regret buying it, but hopefully future models will have worked out the kinks.

Not so sure if it is worth it
I don't do a lot of out of town highway travel, so I'm not sure this really helps me with my local traffic. I have found it very accurate, but if I have chosen the freeway route, I typically already know what the traffic will be like from the TV or radio. Where I do see some value...it helps to make the ETA on the GPS route more accurate. I think if I drove cross country it would help me decide whether to use through town or perimeter routes as I am approaching large cities. It works, I just don't think it does anything for ME on my daily commutes. I often find myself saying, "oh yeah, there's the traffic jam I see on the GPS". In Atlanta, at least, it does nothing for the surface streets.

save your money
I used this for about 2 weeks in the NYC area in December 07. The reports were totally worthless, I was told there was heavy traffic ahead when there was none and not told of traffic and ran into jams without warning. 2 times it reported jams when I ran into them and it was too late. Save your money do not buy any traffic receivers, the technology is too early in development. I wouldn't use it if it was free considering my experience and would rate it "0" Stars if possible. the GPS is great with the NUVI 650 though.