I fitted a set of Train horns onto my Subaru recently
Can be viewed here on Youtube .
Note that I can only physically fit 2 of the 3 air horns !!!!
I was soooooo impressed, that I now have a set fitted on my Transit as well now.
The complete kit comes with Air compressor, Air tank, Air line, wiring and Train Horns.
The kit I have is about the loudest horn I have heard (yet !!) in the UK, I have tooted a couple of trucks with horns fitted on them, and they didn't sound all that loud ....... I have also yet to fit the uprated calve to the horns, it is only on a 1/4" valve at the moment, soon to be 1/2" valve

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I anyone is interested in the full setup as above, it cost me around £230 all in (inc Shipping) from the States ..... Quite a few people have ordered these since seeing/hearing mine

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Here are the full details from the manufacturer in the StatesAll I can class them as, is Excellent
