When I tried to paint the walls in water tank room for redecoration, I needed the paint for the walls about 20L. A 20L paint can is so heavy, it's hard to mix by just using a human power. Instead of using human power, it mixes with the machine that can rotate 360 degrees to make sure the ink is mixed well enough to make a right color that I choose from the color catalog. It would be tough tough to mix if you use your strength to mix it. 😬 P.S. If you choose a color you want from the color catalog, there's an ink machine it measures the exact amount and pours in the lid directly. By using digital ink machine.