Just received this today:
From here: http://screaming-banshee.com/
Wolo 139dB horn and solid State relay combo that flashes the high beams and pulses the air horn. A quick horn tap just sounds the stock horn.
My father's day gift to myself.
I got the chrome one, because I like shiny things. LOUD, shiny things.
Qhwn I get it installed, I'll write a review.