What do I need?

Hey guys, Im new to the forum and need some advice. I plan on adding some train horns to my f250 soon and really want real ones. I am thinking about getting the 540 air system from hornblasters then buying a p3. What else would I need to have a functioning setup? would you recommend the 540 system? all input appreciated, Thanks!

Welcome.
You’ll just have to get air to the horns. So - airline, valve, fittings…
Maybe a couple little things like fuse taps, switches, etc…

any hornblaster kit is a good beginner kit. i pieced together my first set up with the shocker xl horns, 480c viair compressor, 5 gal and a 3/8 valve and i had under 300 in this set up. then said i wanted real ones and finally got a good deal on a set of k5’s at the time for 650 for horns only, bought a 480 viairdual pack, 1/2 gc xtreme 450 valve, 5 gal tank, relay, 1/2 hydraulic hose and have roughly 1100 in a set up that is bullet proof.

Welcome to the forum. I agree, any HB kit with shockers is a good start.