Men's USB Charging LED Shoes Flashing High-Sneaker PU CHARGE INSTRUCTION: Easy charge like your cell phone with the attached USB charging cable.Switch on the shoes when received and light up until all power gone.Then charge both shoes for 3 hours. sole material:crystal-like transparent TPR Do not put the sneakers into water, you can use soft cloth to clean them. It is reasonable if the size difference is within 2-3cm. Compare the chart size with your feet length carefully before ordering