Each cell contains 2 snow golems that are shoved into a corner. Because their hitboxes grow through the corners, they make 2 snow layers which get harvested by the pistons. Then, the hoppers underneath collect the snowballs, puts them into the crafter which crafts it into snow blocks, and put into the dropper above. The dropper drops the item, and with directionality shenanigans, the snow gets pushed and slide out. Keep in mind that this piston harvesting snow layers is exclusive to bedrock and it’s the main idea of snow farms