I just installed the D2's to replace my fog lights. They came with all the wiring, fuse, and switch to install them. I chose to power them from my battery with the included harness and splice them into my switch, I do not have any of the LED flicker and they work just like my fog lights did. I can't speak as to how much difference there is between the Dually's and the D2's, but I am from the camp that says you can never have enough light.
I did have to purchase the mounts to mount them into the bumper, they didn't come with those.
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