I have a hookup in my front bay for towing also. It is a male quick connect with a gate valve. I made an adapter with two female quick connects so that I can hook my air hose to it if needed. I carry a small craftsman that I use for airing tires.
This brings up another question I had. If in the engine air compressor failed, could the system be charged and driven via this connection by my Craftsman and genny to avoid towing?
I'm one of those guys who is always thinking ("if" this happens "then" I'll...). It's a sickness..