These are about 220 grit and good for sanding between coats. I haven't used all of them yet, but the two I've used so far are pretty good. They can be used in a cordless drill and I have also used them in a drill press. Ideal for uneven surfaces and rounded sanding and finishing work. I assume they can also be used to clean metal and oily surfaces like engine and parts cleaning, but I haven't tried that. On dry wood they held up well and didn't fall apart or wear out as expected.