You can make the open side face down first, then pour the particles inside to the open side, then keep the opening below, rotate the box by 180 degrees, make the open side face up, and then press that button, and there will be cleaning particles in the small groove with the opening. This design of Yangshengtang is really unique.

The general idea is to try to get the particles into the open tank first, and then pour them out of the tank. . .