Natural FOOT PADS to Relieve Stress, Improve Sleep. Why do Foot Pads Turn Dark? If Exposed to Water or Sweat. The foot pads will definitely get dark when placed under water or sweat, just like tea bag will get dark, due to the special substance inside. But you will see some differences: Exposed to water or sweat: Only turn dark, just like the tea bag and the surface have nothing - no gooey or other problematic item. Tear off pads from your feet: The foot pads will be brownish gooey and tar like, most likely substance that has been out your feet. If you continue to use it you will notice that they don’t come out gooey in the morning anymore. How to Use Foot Pads? - Clean your feet thoroughly and dry. - Place the printed side of foot pad on center of adhesive sticky sheet. - Attach the foot pad on the arch of the foot. - Pads should be left in place for 6 - 8 hours. - Tear off after getting up in the morning, please do not reuse it. TIPS 1.Worn a light sock over the foot pads to avoid accidental displacement. 2.Only for external use, please do not take orally. 3.Pregnant women and those who have allergies problems are prohibited to use it. 4.Recommend use it continuously for about 2 months when you use it first.