The P115W-S is the right model for all with 3-pin H4 lamps.

 

I always thought it was because high-beams are much more visible in daylight. You could rig a modulator up to work with low-beams or even a second unit with passing lamps, either way by re-routing the pins, and although I can't find any wording in the federal law that would prohibit it I think LEO's might have issues with too many blinking lights. That might invite unwanted attention and perhaps some from other motorists. In six years of use I haven't had anyone react aggressively, but I think three lights flashing might be over the line. They would definitely attract attention, though.

 

I'm a big fan of headlight modulators. I think any of the mentioned units you get will be reliable and make you more visible.

I have the Signal Dynamics unit and I'm very happy with it. Can be switched back and forth from hi to lo or turned off. The biggest problem is it's not plug and play.

 

Thank You!

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