googled and found this quick... haven't ever hardly used it so didn't know off hand..lol... looks like its a thumb operated swith for mostly changing gears? its go a bunch of adjustments under the "blue" case atop the radio too...
If you interested in selling it for next to nothing I might be interested as I have one of these already and couldn't hurt to have another. Or possibly trade for some decals.
Shoot me a PM if your interested.
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