4 Rock Polishing Grit Packs For Tumblers. This is a new set of polishing grits. There are four different grits giving you everything you need to tumble stones. You receive: One 4 Ounce Pack of Coarse Grit. One 4 Ounce Pack of Fine Grit. One 2 Ounce Pack of Polish. One 2 Ounce Pack of Prepolish.