Synthetic Brushes

I dont now

Abrading paper, also known as sandpaper, is used for smoothing and polishing surfaces by rubbing it against the material. It is commonly used in woodworking, metalworking, and other applications to remove rough spots, scratches, or imperfections from surfaces. Different grades of abrasiveness are available to suit different materials and finishing needs.

If u r looking for the waja's word wizard answer, it is plastic. :)

The inner planets' surface materials differ from the outer planets because the inner planets have rocky surfaces and the outer planets have gas surfaces.