Feature: Stretchy: Elastic strap makes it easy and comfortable to wear, won't crack and won't hurt your ears. Free size Comfortable: The material chosen is high quality, which is soft and skin friendly to wear Breathable: The mask is designed in cotton material, making you breathe freely, really comfortable Application: This mouth mask is perfect for running, cycling, hiking or other outdoor activities, it's also suitable for daily use The size :18x13cmPackage Contents: 5PC mask