I have a Take-A-Look on my sunglasses, and it works very well. As long as I remember to apply the anti-fog stuff to it (as well as my sunglasses and glasses) when it's raining. I also have a convex type mirror on the right handlebar for vehicles in town coming up in the right turn lane.
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What do you call a cyclist who sells potpourri on the road? A pedaling petal-peddler.