What is that black junk that appears on the foot pads after wearing them overnight? Is that just dirt from the bottom of your feet or is it some chemical reaction that appears on the surface of the pad so it appears as if it came from your body?
What is that black junk that appears on the foot pads after wearing them overnight? Is that just dirt from the bottom of your feet or is it some chemical reaction that appears on the surface of the pad so it appears as if it came from your body?