Orbital sander sanding sheet by Morris. The sanding grains (grit), contained per square millimeter in the product, amount to K40. The larger the sandpaper number, the greater the density of grains per square millimeter. Therefore, in small numbers (e.g., 24, 36, 40…), we have fewer but larger diameter grains, making them ideal for quickly smoothing rough surfaces, while in large numbers (e.g., 180, 220, 320…), we have more grains with smaller diameter, ideal for intense sanding and smooth finishing. You should also know that when sanding with the sander, the action is significantly greater than by hand. Its dimensions are 225x225mm. The package contains 1 piece.