wow thats really cool. I had no idea they made things like that! 
yes im looking for some thing like that. BUt not around that much money 
is there any other ones? One question I had was what if the out let and inlet of it are 1/4 inch.? for example… 1/2 from take to an 1/4 adapter then to the regulator then back out to 1/2 line… Will i loose air or PSI?
You won’t loose PSI but you will restrict air flow. If your tank has larger ports, use nipples or couplers and stay away from bushings or bell reducers.
Which would mean the horn not being as loud correct?
That would be my guess.
I edited the previous one too.
ahh see i was going to use bell reducers but not now…i have to find me a decent air regulator with 1/2 …thanks dan
Try some web searches for “air pressure regulator”. You might find what your looking for.
dan i find alot of 1/2 reguators but the only problem is they are regualted max at like 125 psi
I would go with the first one for its CFM rating. I think the second one at 5 gallons per minute is too slow. You still need a gauge with either one to know where it’s set.