Steibel Horn

[Robinson, Art (ON15)]

I bought one of these about 2 years on the recommendation of a Lister,
whose name escapes me. (Whoever you are, THANK  YOU!!!)

I finally installed it about a month ago and I'm well pleased. 

One thing I noticed after I completed the installation was an air
connection with a barb on it, as if it was designed to take a 5'16"
hose. 

It struck me that it might be for attaching another horn downstream, but
I've never investigated it to see if it exhausts air when the horn is
activated or if an input for another compressor.

Anyone know what the function of this piece is?

Thanks,

Art in TO