New cleaning apparatus for chalk blackboard erasers (Machine-translation by Google Translate, not legally binding)

摘要

The property and exclusive exploitation of: 1. New slate eraser cleaner for chalks characterized in that it completely eliminates, by rubbing and suction, the chalk powder that impregnates them and stores it inside, allowing it to be disposed of with total cleanliness. (Machine-translation by Google Translate, not legally binding)