Thanks for posting about that 3M product.
I did some web searching on the product and found a PDF file that explains the grit:
3M Industrial Products Catalog: adhesives, tapes, abrasives and more
When page finishes loading, click on the tab Documentation.
Third PDF file in list: Scotch-Brite® Bristle Disks and Brushes -Brochure
(The file is a 8.6MB PDF file.)
Page 4 has tables listing the grit sizes for the varrious disks for the small diameter disks and bristles.
The Pink and Peach color brushes seem to be "pumice" and "6 micron" which would be super fine polishing in my book.
Thank-you Greatdane2 for letting me learn something today.
Phil