12 piece set of 10mm thick sanding sponges with a single grit size of #240 Sponges are harder than other Kamiyasu Sanding Sponges series, ideal for surface treatment. You can cut it into small pieces to polish small surfaces. The ink hardly oozes and is good for wet polish, too. Grit size: #240 size(per piece): approx. 20mm×35mm×10mm Total amount: 12 pieces