What is this flap?

[C Hoov]

Posted this in the general area and didn't get any useable replies (at least none that I could understand) . I found this flap in the front right (passenger) wheel well behind the skirt (or in front of the passenger door) (2001 Tahoe). I have no idea where it came from. It seems to be weighted, looks like a brass weight molded in it. The rubber is totally deteriated. Would like to know if anyone knows what it is before I tear the truck apart looking for its origin.
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[C Hoov]

Anybody? Any Ideas?

 

[chauncey0337]

Never seen it before. Maybe I'll check my truck to see if I have one too. I'm guessing you stumped alot of members with this one but hopefully someone here knows what it is.

 

[C Hoov]

Guess I'll try to take it by a dealer this week to see if they have a clue.