I will raise this one further. I have a set of Denali D4s and I have them powered by a Neutrino Black Box which is a computer controlled version of a fuse box. It can do anything like act like a fuse, dim the lights manually or even automatically (for instance at whatever time sunset is at your location). They can also — and this is where this arrangement is better than the Clearwater flicker apparatus) modulate your headlights for the conspicuosity everyone is looking for in this thread.
I have mine for instance set up so my D4s are at 100 percent on high beam, at 30% and flickering at 4 cycles per second on low beam between half an hour after sunrise and half an hour before sunset and at 40 % on low beam at night. All this happens automatically an is controlled by an app on my iPhone. And because I now have a six function fuse box — where blown fuses are rectified by a flick of my iPhone 6 — I also have my heated gear — set up to turn on automatically at about 55 degrees and to gradually increase in warmth down to 30 degrees — and my battery tender all attached with only two wires to my battery.
Cleaner wiring, headlight modulation, automatically increased heating from my electric vest and a quick detach connection for my battery tender. Tres cool!