I put a flash light inside the shoe to see if they were permeable, and no light showed through. I have a 5-bike bicycle rack installed on this hitch. These shoes have instantly become a favorite of hers! The fit was loose, which I was expecting. Im a very happy with my decision. Very light and actually fit well too. Many of my bow hunting spots require wading through angle deep water. I love this style from the Birkenstock collection - this is my 3rd pair! Overall I would recommend giving these a shot. The company gave me my money back immediately when I asked a question.