Bunch of small feather dusters?

[Krypler]

I was about to clean back chamber and heaters. I came across these. Need ID please. They looks like a overload of small feather dusters.

should I leave or still clean out chambers?

 

[Tired]

Those are in fact small feather dusters. They'll hang out back there and eat particles. Unless there are so many that they're obscuring the flow and causing problems, they're fine.