This is a great eco-friendly alternative to deodorizing your shoes. The only difficulty I find is that in order for them to work they have to sit out in the sun for a few hours. It is hard for me to remember to do that once a month sometimes. I find that these work very well my gym shoes always had an odor to them, but this helped to take most of the smell away. This is available on Amazon . I received this product at a discounted rate in exchange for a honest review.