I bought these because the anemic single tone horn on my 2020 Nissan Versa was absolutely pathetic. It's already a go-kart, but with the horn on I felt even less visible on the road. I didn't need a relay or anything, I just made a Y splitter with wire cuts and clamps. It comes with thin metal strips that can be attached to the car frame. Super easy, much better. Other drivers can now hear my horns even if they can't see them.
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