Those cover things aren't a bad I idea. I'd thought about one at one point.
Imo, if you're want to keep the radio dry in case you get caught topless in the rain, get a windjammer...most of the rain getting up front when you're topless in the rain (& moving) is from the back of the jeep.
I actually did a 3hr drive topless with a windjammer, from one coast of FL to the other & it was raining the whole time. Some of the rain on the trip got pretty heavy, but with the windjammer on, I/the radio/the windshield stayed dry.
...well I got wet in traffic & on some on/off ramps...but hardly wet
Obviously, in FL there's lots of rain & as much as I try to avoid it, I've driven topless in rain multiple times.
My alpine headunit has gotten wet multiple times & works perfectly. I try not to let water get "in" it though.
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