you need airflow....not a lot, but enough to get rid of the stale air in the box at least every 5 minutes....so at least a hole near the bottom for air intake, and a computer fan or small table fan up near the top to pull air through the box. Obviously not blowing directly on your drying buds, but enough to keep circulation around them. Mold/mildew will develop otherwise. And you need to have some kind of way to tell the humidity inside, so get yourself a hydrogemeter or something and try to keep humidity below 65%.