Inside my Hole?

[steamron]

I was cleaning up my TM, Prochem Apex, while looking inside my exhaust I saw this.

What is it??

http://s1324.photobucket.com/user/cleanerguy/media/IMG_20131117_203953_zps86af91be.jpg.html

 

[Jim Martin]

 

[FredC]

helps direct exhaust out of exchanger?

 

[floorguy]

yup and of course the exchanger

 

[Shawn Abbey]

It probably keeps the hot air in the chamber longer to better heat the water.