The fermentation lock or airlock is a device used in beer brewing and wine making that allows carbon dioxide released by the beer to escape the fermenter, while not allowing air to enter the fermenter, thus avoiding oxidation.
Most wood blinds are treated with a special finish to repel dirt and stains. Wood blinds can be cleaned with a good quality furniture polish and a soft cloth or clean sock. Spray the furniture polish on the cloth and wipe each slat individually. Avoid touching the cords. For heavier cleaning, you can use plain water, but be careful not to saturate the wood.
The doorway should have a lip of about one-inch above the floor to help keep the babies in the box (until they are old enough to venture out on their own.) Place a large handful of straw, grass or hay in the box and place it in a corner of the rabbit cage. Be sure it is not in the corner that she uses as a bathroom! Make sure that grass clippings do not contain any pesticides or fertilizers.