These are either tumbleweed seeds or insulation quality indicators.
If the latter, and presuming they are working correctly, they suggest your attic is under insulated. They will only operate when escaping heat is exits via the attic and melts snow, which freezes at the eaves, where the roof and the outside temperature are equal.
No offense, but I think these are the cheap version. Mine were more heavy duty and looked suspiciously like dams.
The reason I have what you want is, I never lent it out before.
Scraps are a myth.