Boric acid powder has numerous uses for the control of insects. Various armies have used boric acid for the control of foot odour and pests for a long time. Mites love to infest clothes and shoes. Boric acid kills mites. Combine them together and save your shoes. What you will need: A clear plastic box or a plastic bag; and mite infested shoes. The box would probably need to be 10L or so in size. The boric acid can be re-used. It is contact poison against mites. In the morning or when the shoes are required.