Veseys

The mini hand seeder works really well for small seeded vegetables that you want to plant fairly thick, but still want to space regularly. It is best with carrots, leaf lettuce, beets/swiss chard, radish, mesclun mixes, bunching onions, radishes and some direct seeded herbs like basil or summer savoury. There is a turn dial on the seeder that adjusts to the small size seed.

From the picture, I can not figure out how this device can do the job. How it work? The picture shown like it is a jar with duck mouth? How this device able to control the amount of the seed that exit the mouth?