Puzzled

Can someone tell me what the "thing" that hose #2 is connected to is??? The reason I ask is these hoses are not in the best shape and i'm wondering if I should replace them.

http://i142.photobucket.com/albums/r100/mrbizness1/blazerexaust.jpg

Looks like a secondary air injection pump...

http://i142.photobucket.com/albums/r100/mrbizness1/blazerexaust.jpg

Same as this 'other guy' posted...

My son's 2000 s10 4.3 blazer has this problem. A rubber hose that is part of a pipe system that travels around the engine compartment is forced off the pipe. It comes from the exhaust manifold near the air box on the left side of the motor. The first time it came off it melted part of the air box. This seems to be part of the exhaust and emissions system but I am not sure.
Can anyone advise me what this is for.
Thanks for any advise

http://i142.photobucket.com/albums/r100/mrbizness1/blazerexaust.jpg

http://i142.photobucket.com/albums/r100/mrbizness1/hoseconnection.jpg

Even has the same photobucket username. How 'bout that???

It is his diagram......... I was reading his thread, saw the diagram, had a question,and borrowed the diagram.