Good point Ryan.
I use a bit of some sort of nylony material meant to be a tacky addition to the edges of curtains. It repels water to a certain degree, drys quickly, and is light enough that it floats on the wind and doesn't swing, but heavy enough that it also doesn't just swing around.
As said, it only tells you what is happening at the muzzle, and can be fooled by objects close to it causing an eddy, such as your body, or a large tree... but it does tell you something at least. Like all tools, you need to know when to use it, and when to leave it aside.
I have mine hanging off to the left, which means i can see it when it points left and right, and also i can position it so my 2nd eye can superimpose it onto the scope eye's view.
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